FILE SYSTEMSFILE SYSTEMS
File SystemsFile Systems
File organizationFile organization Access methodsAccess methods Directory Organization single two-Directory Organization single two-
level hierarchylevel hierarchy File system and directory File system and directory
implementationimplementation Allocation schemes contiguous Allocation schemes contiguous
linked indexedlinked indexed
File system File system
In a computer a file system (sometimes written In a computer a file system (sometimes written filesystem) is the way in which files are named and filesystem) is the way in which files are named and where they are placed logically for storage and where they are placed logically for storage and retrieval retrieval
The logical unit within a file system is the fileThe logical unit within a file system is the file logical files are mapped into physical entities by logical files are mapped into physical entities by
the OSthe OS in users view file is the smallest unit that can be in users view file is the smallest unit that can be
saved to disksaved to disk
A file system defines the structure and the rules A file system defines the structure and the rules used to read write and maintain information used to read write and maintain information stored on a disk stored on a disk
Which system used is determined byWhich system used is determined by HardwareHardware SoftwareSoftware Security needsSecurity needs Need for a dual-booting systemNeed for a dual-booting system
File AttributesFile Attributes namename provides handle for reference provides handle for reference
bull bull DOS (8 chars + 3 char extension) Windows DOS (8 chars + 3 char extension) Windows (unlimited length)(unlimited length)
bull bull UNIX (spaces tricky no extension needed)UNIX (spaces tricky no extension needed)
type type indicates how the file should be treated indicates how the file should be treated
bull bull DOSWindows rely on extension can map DOSWindows rely on extension can map extensions to programsextensions to programs
bull bull Mac associates creator attribute with each file (OS Mac associates creator attribute with each file (OS X)X)
bull bull UNIX uses magic number first few bytes of file UNIX uses magic number first few bytes of file specify file typespecify file type
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File SystemsFile Systems
File organizationFile organization Access methodsAccess methods Directory Organization single two-Directory Organization single two-
level hierarchylevel hierarchy File system and directory File system and directory
implementationimplementation Allocation schemes contiguous Allocation schemes contiguous
linked indexedlinked indexed
File system File system
In a computer a file system (sometimes written In a computer a file system (sometimes written filesystem) is the way in which files are named and filesystem) is the way in which files are named and where they are placed logically for storage and where they are placed logically for storage and retrieval retrieval
The logical unit within a file system is the fileThe logical unit within a file system is the file logical files are mapped into physical entities by logical files are mapped into physical entities by
the OSthe OS in users view file is the smallest unit that can be in users view file is the smallest unit that can be
saved to disksaved to disk
A file system defines the structure and the rules A file system defines the structure and the rules used to read write and maintain information used to read write and maintain information stored on a disk stored on a disk
Which system used is determined byWhich system used is determined by HardwareHardware SoftwareSoftware Security needsSecurity needs Need for a dual-booting systemNeed for a dual-booting system
File AttributesFile Attributes namename provides handle for reference provides handle for reference
bull bull DOS (8 chars + 3 char extension) Windows DOS (8 chars + 3 char extension) Windows (unlimited length)(unlimited length)
bull bull UNIX (spaces tricky no extension needed)UNIX (spaces tricky no extension needed)
type type indicates how the file should be treated indicates how the file should be treated
bull bull DOSWindows rely on extension can map DOSWindows rely on extension can map extensions to programsextensions to programs
bull bull Mac associates creator attribute with each file (OS Mac associates creator attribute with each file (OS X)X)
bull bull UNIX uses magic number first few bytes of file UNIX uses magic number first few bytes of file specify file typespecify file type
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File system File system
In a computer a file system (sometimes written In a computer a file system (sometimes written filesystem) is the way in which files are named and filesystem) is the way in which files are named and where they are placed logically for storage and where they are placed logically for storage and retrieval retrieval
The logical unit within a file system is the fileThe logical unit within a file system is the file logical files are mapped into physical entities by logical files are mapped into physical entities by
the OSthe OS in users view file is the smallest unit that can be in users view file is the smallest unit that can be
saved to disksaved to disk
A file system defines the structure and the rules A file system defines the structure and the rules used to read write and maintain information used to read write and maintain information stored on a disk stored on a disk
Which system used is determined byWhich system used is determined by HardwareHardware SoftwareSoftware Security needsSecurity needs Need for a dual-booting systemNeed for a dual-booting system
File AttributesFile Attributes namename provides handle for reference provides handle for reference
bull bull DOS (8 chars + 3 char extension) Windows DOS (8 chars + 3 char extension) Windows (unlimited length)(unlimited length)
bull bull UNIX (spaces tricky no extension needed)UNIX (spaces tricky no extension needed)
type type indicates how the file should be treated indicates how the file should be treated
bull bull DOSWindows rely on extension can map DOSWindows rely on extension can map extensions to programsextensions to programs
bull bull Mac associates creator attribute with each file (OS Mac associates creator attribute with each file (OS X)X)
bull bull UNIX uses magic number first few bytes of file UNIX uses magic number first few bytes of file specify file typespecify file type
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
A file system defines the structure and the rules A file system defines the structure and the rules used to read write and maintain information used to read write and maintain information stored on a disk stored on a disk
Which system used is determined byWhich system used is determined by HardwareHardware SoftwareSoftware Security needsSecurity needs Need for a dual-booting systemNeed for a dual-booting system
File AttributesFile Attributes namename provides handle for reference provides handle for reference
bull bull DOS (8 chars + 3 char extension) Windows DOS (8 chars + 3 char extension) Windows (unlimited length)(unlimited length)
bull bull UNIX (spaces tricky no extension needed)UNIX (spaces tricky no extension needed)
type type indicates how the file should be treated indicates how the file should be treated
bull bull DOSWindows rely on extension can map DOSWindows rely on extension can map extensions to programsextensions to programs
bull bull Mac associates creator attribute with each file (OS Mac associates creator attribute with each file (OS X)X)
bull bull UNIX uses magic number first few bytes of file UNIX uses magic number first few bytes of file specify file typespecify file type
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File AttributesFile Attributes namename provides handle for reference provides handle for reference
bull bull DOS (8 chars + 3 char extension) Windows DOS (8 chars + 3 char extension) Windows (unlimited length)(unlimited length)
bull bull UNIX (spaces tricky no extension needed)UNIX (spaces tricky no extension needed)
type type indicates how the file should be treated indicates how the file should be treated
bull bull DOSWindows rely on extension can map DOSWindows rely on extension can map extensions to programsextensions to programs
bull bull Mac associates creator attribute with each file (OS Mac associates creator attribute with each file (OS X)X)
bull bull UNIX uses magic number first few bytes of file UNIX uses magic number first few bytes of file specify file typespecify file type
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
protection permissions access control informationbull UNIX utilizes permission string chmod 644 footxt 1048774 -rw-r--rmdashowner amp group chown chgrpbull Windows utilizes file propertiesattributes NoAccess List Read Read amp Add hellip
Location amp Size
Accounting Information
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
eg MS-DOS filename eg MS-DOS filename
Filename 1 to 8 charactersFilename 1 to 8 characters File extension 1 to 3 charactersFile extension 1 to 3 characters DOS only uses uppercaseDOS only uses uppercase You cannot use spacesYou cannot use spaces A single period separates the file extension from A single period separates the file extension from
the filenamethe filename You cannot use these charactersYou cannot use these characters
ldquo lt gt | + = [ ] ldquo lt gt | + = [ ]
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
The Full PathThe Full Path
What does it meanWhat does it mean The complete path from the root of the files The complete path from the root of the files
system to the desired objectsystem to the desired object Use Use (vs ) (vs ) C - the rootC - the root
For ExampleFor Example
EBSIT6th SemesterSystem AdministrationFile EBSIT6th SemesterSystem AdministrationFile SystempptSystemppt
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File Names continuedFile Names continued
Filenames consist of two partsFilenames consist of two parts Main part of filenameMain part of filename
Identifies the contents of the fileIdentifies the contents of the file File extensionFile extension
Identifies the file typeIdentifies the file type The last period separates the file extension from The last period separates the file extension from
the main part of the filenamethe main part of the filename Windows typically associates a file extension with Windows typically associates a file extension with
an application installed on a computeran application installed on a computer
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Folder NamesFolder Names
Folder names follow the same guidelines for Folder names follow the same guidelines for naming files naming files
Folder names usually do not have a file extensionFolder names usually do not have a file extension
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File OperationsFile Operations create find space on disk and make entry in create find space on disk and make entry in
directorydirectory write write to file requires positioning within the write write to file requires positioning within the
filefile read read from file involves positioning within read read from file involves positioning within
the filethe file delete delete directory entry reclaim disk spacedelete delete directory entry reclaim disk space reposition move readwrite positionreposition move readwrite position
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
the OS must maintain the OS must maintain information about all open information about all open
filesfiles file pointer the current position of the readwrite file pointer the current position of the readwrite
pointer in the filepointer in the file disk location the location of the file on the diskdisk location the location of the file on the disk file open count keep track of number of file open count keep track of number of
processes currently accessing the fileprocesses currently accessing the file
such a table of information allows the OS to such a table of information allows the OS to enforce policies such as only one process can enforce policies such as only one process can write to a file at a given timewrite to a file at a given time
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File StructureFile Structurefiles can be stored physically asfiles can be stored physically as BytesBytes LinesLines recordsrecords
whatever entity is stored OS must map whatever entity is stored OS must map into a disk sectorinto a disk sector
because on a physical disk sectors are because on a physical disk sectors are smallest writeable unit smallest writeable unit
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
access methodsaccess methods sequential information in the file is accessed from first sequential information in the file is accessed from first
to lastto last readNext writeNext resetreadNext writeNext reset direct possible to reposition readwrite pointer to any direct possible to reposition readwrite pointer to any
positionposition such files are generally made up of fixed-length recordssuch files are generally made up of fixed-length records readRecord N writeRecord N positionAt N resetreadRecord N writeRecord N positionAt N reset indexed built on top of direct access but accesses indexed built on top of direct access but accesses
records in file using a keyrecords in file using a key each record has a key associated with it an index of each record has a key associated with it an index of
keys is stored with the filekeys is stored with the file readRecord KEY writeRecord KEY positionAt KEY resetreadRecord KEY writeRecord KEY positionAt KEY reset
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
FATFAT
file allocation table ndash where the OS records how the file allocation table ndash where the OS records how the disk space is useddisk space is used
locates the file allocation table near the beginning locates the file allocation table near the beginning of the volumeof the volume
the location of the FAT is specified in the boot the location of the FAT is specified in the boot sector (BIOS Parameter Block)sector (BIOS Parameter Block)
actually 2 copies of the FAT are stored for actually 2 copies of the FAT are stored for redundancyredundancy
the FAT number refers to the number of bits per the FAT number refers to the number of bits per table entrytable entry
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File SystemsFile Systems
FAT12FAT12 The earliest version the file system The earliest version the file system FAT12 allows a partition to contain up to 4096MB FAT12 allows a partition to contain up to 4096MB (212)clusters(212)clusters
FAT 16FAT 16 oldest created for DOS supported by oldest created for DOS supported by most OSrsquos cannot be installed on partitions larger than most OSrsquos cannot be installed on partitions larger than 2 GB or on hard drives larger than 4GB2 GB or on hard drives larger than 4GB
FAT 32FAT 32 supports disks from 512MB to 2TB supports disks from 512MB to 2TB compatible with Windows 98 and upcompatible with Windows 98 and up
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
ContdContd
the FAT number refers to the number of the FAT number refers to the number of bits per table entrybits per table entry
FAT12 -gt 212 = 4M different clusters FAT12 -gt 212 = 4M different clusters can be addressed (used for floppy disks)can be addressed (used for floppy disks)
FAT16 -gt 216 = 64M different clusters FAT16 -gt 216 = 64M different clusters can be addressed (MS-DOS compatible)can be addressed (MS-DOS compatible)
FAT32 -gt 228 = 256G different clusters FAT32 -gt 228 = 256G different clusters (4 bits are reserved)(4 bits are reserved)
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Advantages of FAT File Advantages of FAT File SystemSystem
The FAT file system is best for drives andor The FAT file system is best for drives andor partitions under approximately 200 MBpartitions under approximately 200 MB
It is better to format system partition as FATIt is better to format system partition as FAT
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Disadvantage of FAT File Disadvantage of FAT File SystemSystem
It is not better to use FAT on partitions that are It is not better to use FAT on partitions that are greater than 200 megabytes FAT partitions are greater than 200 megabytes FAT partitions are limited in size to a maximum of 4 Gigabytes (GB) limited in size to a maximum of 4 Gigabytes (GB) under Windows NT and 2 GB in MS-DOSunder Windows NT and 2 GB in MS-DOS
Any FAT partitions that use DOS-based disk Any FAT partitions that use DOS-based disk compression (such as DriveSpace) will not have compression (such as DriveSpace) will not have readable files when running Windows NTreadable files when running Windows NT
The FAT file system is also prone to fragmentationThe FAT file system is also prone to fragmentation
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
NTFSNTFS New technology file systemNew technology file system Better file security (Encrypting File Better file security (Encrypting File
System)System) Disk compression- can compress a Disk compression- can compress a
filefolder any Windows app will filefolder any Windows app will automatically expand as neededautomatically expand as needed
Disk Quota features-Disk Quota features- Can enforce Can enforce quotas on disk usagequotas on disk usage
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
ContdContd
Recovery features-each file operation Recovery features-each file operation broken down into atomic transactionsbroken down into atomic transactions
maintains a maintains a transaction log transaction log ndash updates ndash updates disk after each transactiondisk after each transaction
if if failurefailure occurs during a transaction info occurs during a transaction info is sufficient to complete or rollbackis sufficient to complete or rollback
if a if a bad sectorbad sector is found when writing will is found when writing will automatically map to a different sectorautomatically map to a different sector
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
NTFS volumes can not be accessed NTFS volumes can not be accessed by DOS by DOS or Windows 95 or Windows 98or Windows 95 or Windows 98
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Advantages of NTFSAdvantages of NTFS
Large disks and large files Large disks and large files NTFS is NTFS is
best for use on volumes of about 400 MB or morebest for use on volumes of about 400 MB or more RecoverabilityRecoverability The recoverability The recoverability
designed into NTFS is such that a user should designed into NTFS is such that a user should never have to run any sort of disk repair utility on never have to run any sort of disk repair utility on an NTFS partitionan NTFS partition
SecuritySecurity NTFS uses the Windows NT object NTFS uses the Windows NT object model to enforce security An open file is model to enforce security An open file is implemented as a file object with a security implemented as a file object with a security descriptor that defines its security attributesdescriptor that defines its security attributes
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
General indexing facilityGeneral indexing facility NTFS NTFS associates a collection of attributes with each file associates a collection of attributes with each file The set of files in the file management system is The set of files in the file management system is organized as a relational database so that files organized as a relational database so that files can be indexed by any attributecan be indexed by any attribute
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Disadvantages of NTFSDisadvantages of NTFS
It is not recommended to use NTFS on a volume It is not recommended to use NTFS on a volume that is smaller than approximately 400 MBthat is smaller than approximately 400 MB
Currently there is no file encryption built into Currently there is no file encryption built into NTFSNTFS ndash encryption is available as an external ndash encryption is available as an external option option
It is not possible to format a floppy disk with the It is not possible to format a floppy disk with the NTFS file systemNTFS file system
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
File SystemsFile Systems
The operating system keeps track of data The operating system keeps track of data (documents pictures etc) by placing it into a file (documents pictures etc) by placing it into a file
To store and retrieve filesTo store and retrieve files Disk divided into tracksDisk divided into tracks Tracks are divided into sectorsTracks are divided into sectors Sectors grouped into clustersSectors grouped into clusters
Number of sectors in a cluster is determined Number of sectors in a cluster is determined byby
Size of the hard driveSize of the hard driveFile allocation system ndash FAT FAT32 NTFSFile allocation system ndash FAT FAT32 NTFS
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Tracks
Sectors within a
Track
Cluster
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
A A clustercluster also known as an allocation unitalso known as an allocation unit consists consists of one or more sectors of storage space and of one or more sectors of storage space and represents the minimum amount of space that an represents the minimum amount of space that an operating system allocates when saving the operating system allocates when saving the contents of a file to a diskcontents of a file to a disk
The number of sectors per cluster is dependent on The number of sectors per cluster is dependent on Type of disk (floppy disk hard disk)Type of disk (floppy disk hard disk) Version of operating systemsVersion of operating systems Size of diskSize of disk
Every sector contains 512 bytes (NTFS does allow Every sector contains 512 bytes (NTFS does allow you to change this number)you to change this number)
The number of clusters per disk is determined by The number of clusters per disk is determined by the filing system (FAT 16 FAT 32 or NTFS) the filing system (FAT 16 FAT 32 or NTFS)
ClustersClusters
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
DRIVE SIZEDRIVE SIZE FAT 16FAT 16Cluster SizeCluster Size
FAT 32FAT 32Cluster SizeCluster Size
NTFSNTFSCluster SizeCluster Size
260 to 511 260 to 511 MBMB
8 KB 8 KB Not SupportedNot Supported 512 bytes512 bytes
512 to 1023 512 to 1023 MBMB
16 KB16 KB 4 KB4 KB 1KB1KB
1024 MB to 2 1024 MB to 2 GBGB
32 KB32 KB 4 KB4 KB 2 KB2 KB
2 to 4 GB2 to 4 GB 64 KB64 KB 4 KB4 KB 4 KB4 KB
4 to 8 GB4 to 8 GB Not SupportedNot Supported 4 KB4 KB 4 KB4 KB
8 to 16 GB8 to 16 GB Not SupportedNot Supported 8 KB8 KB 4 KB4 KB
16 to 32 GB16 to 32 GB Not SupportedNot Supported 16 KB16 KB 4 KB4 KB
gt32 GB gt32 GB (up to 2 (up to 2 TB)TB)
Not SupportedNot Supported 32 KB32 KB 4 KB4 KB
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
OS and File System OS and File System CompatibilityCompatibility
Operating SystemOperating System FAT16FAT16 FAT32FAT32 NTFSNTFS
Windows XPWindows XP
Windows 2000Windows 2000
Windows NTWindows NT
Windows 95 98 MEWindows 95 98 ME
Windows 95Windows 95
MS-DOSMS-DOS
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
What happens during the What happens during the Formatting ProcessFormatting Process
OS creates four tables in the 1OS creates four tables in the 1stst sectors sectorsBoot RecordBoot Record ndash the name amp version number of ndash the name amp version number of the OS info on the physical characteristics of the OS info on the physical characteristics of the diskthe diskMaster File Table 1-Master File Table 1- keeps track of keeps track of
Available clustersAvailable clustersClusters that contain dataClusters that contain dataClusters that are defectiveClusters that are defectiveClusters that contain OS filesClusters that contain OS files
Master File Table 2Master File Table 2 ndash copy of MFT 1 ndash copy of MFT 1Directory TableDirectory Table ndash top level folder and file ndash top level folder and file informationinformation
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Formatting Process contFormatting Process cont
Full FormatFull Format lays down new tracks and sectorslays down new tracks and sectors Verifies the integrity of each sectorVerifies the integrity of each sector
By doing a surface scan ndash OS will put dummy By doing a surface scan ndash OS will put dummy data into sectors and then try to read the data into sectors and then try to read the sectorsector
Quick FormatQuick Format Removes filesRemoves files Does not check for defective sectorsDoes not check for defective sectors
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Formatting Process contFormatting Process cont
Should you Should you format brand format brand new new preformatted preformatted diskdisk
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Registered FilesRegistered Files
A file that is associated with an application on A file that is associated with an application on your computer via its file extensionyour computer via its file extension
Where is this information keptWhere is this information kept
THE REGISTRY ndash a database that consists of a set THE REGISTRY ndash a database that consists of a set of files where Windows XP stores your computerrsquos of files where Windows XP stores your computerrsquos hardware software network securityuser hardware software network securityuser settings or profiles and property settings for settings or profiles and property settings for folders and programsfolders and programs
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Compare FAT and NTFS Compare FAT and NTFS File SystemFile System
CompatibilityCompatibility Only Windows NT supports NTFS partitions Only Windows NT supports NTFS partitions
Windows NT and Windows 95 supports both NTFS Windows NT and Windows 95 supports both NTFS and FATand FAT
Volume sizeVolume size FAT supports partition sizes only up to 2 GB FAT supports partition sizes only up to 2 GB
the maximum size of an NTFS partition is 16 EB the maximum size of an NTFS partition is 16 EB
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Fault toleranceFault tolerance Windows NT offers software support for several Windows NT offers software support for several
alternate disk-access methods that increase alternate disk-access methods that increase speed andor fault tolerance While FAT does speed andor fault tolerance While FAT does maintain two copies of the file-allocation table in maintain two copies of the file-allocation table in case one copy is damaged itrsquos incapable of case one copy is damaged itrsquos incapable of automatically fixing errorsautomatically fixing errors))
File compressionFile compression NTFS has its native support for file compression NTFS has its native support for file compression
It offers you the chance to compress individual It offers you the chance to compress individual files and directories of your choice files and directories of your choice
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
The system partition The system partition A better solution is to format your system partition A better solution is to format your system partition
as FATas FAT because because NTFS partitions are accessible only NTFS partitions are accessible only via Windows NT If you have a fatal error with via Windows NT If you have a fatal error with Windows NTWindows NT you canrsquot simply boot a system disk to you canrsquot simply boot a system disk to a command prompt and fix a problem on an NTFS a command prompt and fix a problem on an NTFS partitionpartition
Converting to NTFSConverting to NTFS In MS-DOS type command CONVERT drive In MS-DOS type command CONVERT drive
FSNTFSFSNTFS
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
SecuritySecurity NTFS has a built-in security systemNTFS has a built-in security system FAT has no FAT has no
local protection it only has the share permission local protection it only has the share permission (protect the file from network(protect the file from network
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Ext3 third extended file Ext3 third extended file systemsystem
Stephen TweedieStephen Tweedie November2001November2001 Journaled file system commonly used by linuxJournaled file system commonly used by linux (journaling capability means no worrying about (journaling capability means no worrying about
metadata corruption What is most noticeable is metadata corruption What is most noticeable is that you can switch back and forth between ext2 that you can switch back and forth between ext2 and ext3 on a partition without any problem it is and ext3 on a partition without any problem it is just a matter of giving the mount command the just a matter of giving the mount command the right file system type )right file system type )
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
AdvantagesAdvantages
(over ext2 file system)(over ext2 file system)
SimpleSimple Have the facility of backup and restore dataHave the facility of backup and restore data journaling improves reliabilityjournaling improves reliability
indexing for larger directoriesindexing for larger directories
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Size limitsSize limits
Block Block sizesize
Max file Max file sizesize
Max filesystem Max filesystem sizesize
1 KB1 KB 16 GB16 GB 2 TB2 TB
2 KB2 KB 256 GB256 GB 8 TB8 TB
4 KB4 KB 2 TB2 TB 16 TB16 TB
8 KB8 KB 2 TB2 TB 32 TB32 TB
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Journaling levels Journaling levels
There are three levelsThere are three levels
Journal (lowest risk)Journal (lowest risk) Ordered (medium risk) Ordered (medium risk) Write back (highest risk)Write back (highest risk)
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
Both metadata and file contents are written to the Both metadata and file contents are written to the journal before being committed to the main file journal before being committed to the main file system system
Only metadata is journaled file contents are not but Only metadata is journaled file contents are not but its guaranteed that file contents are written to disk its guaranteed that file contents are written to disk before associated metadata is marked as committed before associated metadata is marked as committed in the journalin the journal
Only metadata is journaled file contents are not Only metadata is journaled file contents are not The contents might be written before or after the The contents might be written before or after the journal is updated journal is updated
ThanksThanks
ThanksThanks
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