Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to...

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Backup & Restore • The purpose of backup is to protect data from loss. • The purpose of restore is to recover data that is temporarily unavailable due to some unexpected event.

Transcript of Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to...

Page 1: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup & Restore

• The purpose of backup is to protect data from loss.

• The purpose of restore is to recover data that is temporarily unavailable due to some unexpected event.

Page 2: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup

To backup or not to back up, that is the question.– Backup is not free.– No backup is risky.

Page 3: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Proper Backup Procedure

• Choose your application

• Scheduling

• Implementation

• Inventory (content and media)

• Verify

• Automate

• Secure

Page 4: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Factors

• Determine which data is critical.

• Determine frequency and types of backups to be used.– Full– Differential– Incremental

Page 5: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Factors

• Determine which data is static and which is dynamic.– Some OS installations are changed

infrequently; few backups required– E-commerce may require continuous backups.– Understand the changing state of your client’s

data to determine an appropriate backup sched.– Organize with partitions

Page 6: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Factors

• Determine the appropriate media storage for your backups:– CD– DVD– Tape– Disk– Solid State?

Page 7: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Factors

• Partitioning of disk space is used to manage backups

Page 8: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Choose your Backup App

• Mac OS X : – Time Machine

• Linux/Unix : – tar (tape archive), cpio, dump

• MS Windows :– MS Windows XP & 7 includes Backup &

Restore capability– Many commercial apps are available

Page 9: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Enterprise Level Backup Apps

• Paragon Backup & Recovery includes customer support

• Backup4All Professional

• GRBackPro7

Page 10: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Schedule

• Determine the categories of data so you can schedule the backups accordingly

Page 11: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Schedule

• Partitions are often used to manage backups

• Examples:– The OS has its own partition and may require

infrequent backups if changes are quarterly– User data may require nightly backups– Users must know what partitions have backup

and the frequency (SLA).

Page 12: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Schedule

• Full Archival Backup– image backup implies copying the unused

space.

• Differential Backup – what has changed since the last backup

• Incremental Backup – what has changed since the last backup of anytype

Page 13: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Full Archival Backup

• Mirror – every last bit on the disk is duplicated.

• Many full backups ignore empty space.

Page 14: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Full Archival Backup (Pros)

Pros

• Provides a complete copy of data

• Easy to manage: – Done less frequently than other types of

backups due to cost and resource requirements:

Monthly, Quarterly, semi-annually, annually.

Page 15: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Full Archival Backup (Cons)

Cons

• Usually requires more media space than either differential or incremental.

• Takes a long time to recover the full backup to a new disk.

Page 16: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Full Archival Backup

• Consider making multiple backup copies• Full backup media should be stored offsite to

protect data from disasters– Fire, Flood, Earthquake, Terrorist attack, Sabotage,

Hacker attacks

Page 17: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Full Archival Backups

• The trend is to reduce the cycle of full backups. This is because of liability. Files that are not backed up cannot be subpoenaed.

• Statute may require destruction of some records.

Page 18: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Differential Backup

• Copy files changed since the last full backup.

• Differential backups grow with time. They can eventually grow larger than the last full backup.

• Scheduled less frequently than a full backups: Weekly, monthly.

Page 19: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Differential Backup (Pros)

• Redundancy

• Usually takes up less time and space than a full backup.

• If the differential backup grows to the size of the last full backup, then schedule a new full backup.

Page 20: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Differential Backup (Cons)

• Redundancy – potentially many unneeded copies of the same data.

• Subsequent differentials take longer and use more media space.

Page 21: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Incremental Backups

• A backup of what has changed since the last previous backup of any type.

• Frequency of incremental backups depends on the client needs.– Weekly, daily, hourly, continuously.

Page 22: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Incremental Backups

• Pros– Keeps a revision history of actively changing

files– Fastest backup type– Uses the least amount of media to complete a

single backup

• Cons– Much more difficult to manage

Page 23: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Schedule Example

• Full backup twice per year

• Differential each first Saturday morning of each month that is not scheduled for a full backup

• Incremental each Saturday morning that is not scheduled for a Full or Differential

Page 24: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Other Schedule Considerations

• Consider completing a backup in conjunction with and before any major system changes are scheduled.

Page 25: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

The Actual Backup

• Assignment of responsibilities– Written in the SA’s job description

• Acceptance of accountability– A signed form indicating that the backup was

complete, verified and secured

Page 26: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

The Actual Backup

• Hardware– Choose the media type– Centralize the backup to reduce redundancy of

hardware– Not everyone archives the local “C-Drive” on

general purpose workstations. (SLA and user awareness)

Page 27: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup Inventory

• Inventory the backup media– Tapes and other writable media use barcodes or

hand-written labels

• Inventory the content of the media– The backup should have a table of contents

included in the backup

Page 28: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup Inventory

• The media label information:– Date– System identifier– Partition name(s)– Backup category: full, differential, incremental

Page 29: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Verify

• The only time you know the quality of your backup media is when you are doing a restore.

• This is the worse time to discover you have problems.

• Restore a small subset of random files from the backup. Verify their integrity through differences or checksums.

Page 30: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Verify: Firedrills

• When new equipment arrives, test your backup procedure on the new equipment to verify it works correctly

Page 31: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup Automation

• Automation reduces human errors.

• Many pre-packaged apps include automatic scheduling

• Linux/Unix backup scripts can be submitted using the cron utility. Logs can be kept in /var/log, and e-mail can be sent to the admin.

Page 32: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Secure The Backup

• Offsite storage

• Encryption: to encrypt or not to encrypt, …– Will the encryption key always be available?– Statute or contract (SLA) may require

encryption

Page 33: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Secure: Off-Site Storage

Off site storage has risks all its own– Data can be lost/destroyed in transit– How important is it to have a backup of the

backup?– Some backups can be kept on site

Page 34: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Secure: Example Strategy

Where the backup is stored will impact service response to restore requests:– Consider keeping incremental backups on site.– Differential and full backups could be stored

offsite.

Page 35: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Data Compression

• Risks – if the media is damaged, recovery may be difficult or impossible.

• Lossy – some data tolerates degradation (loss of

information)

• No-loss – Some data should not be compressed. Know

your data!

Page 36: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Secure Backups

• Contract to store your data in a “secret” offsite location. (Secret implies a need to know basis)

Page 37: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup Considerations

• Backups slow down service. This should be included in the SLA– Files should be write-locked during backup.

• Avoid doing backups during peak service hours. Schedule during early AM hours on the weekend and holidays.

Page 38: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Restore

• Common reasons for restores– Accidental file deletion– Disk failure– Disaster recovery

• Fire, flood, earthquake, hacker attack, sabotage, terrorist attack, etc.

Page 39: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Accidental File Deletion

• If backups are once per day, lost work is limited to one day for a given file. (RAID does not help)

• As storage technology gets cheaper by the Gbyte, it becomes easier to implement more sophisticated storage procedures that are more timely. (HDD backup).

• A user wants the restoration to be immediate. The quicker the turnaround, the happier your customer.

Page 40: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Disk Failure

• A disk failure causes two problems– Loss of data– Loss of service

• Critical systems should implement RAID so that disk failures do not cause a loss of service.

• Restoring an entire disk is slow. Service is hampered until the last bit is recovered.– Consider using hot spares and hot swap

Page 41: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Disk Restore from Tape

• Restoring from tape can interrupt service.

• Restoring from tape slows the restore process by a factor of about 5-10 times compared to a simple disk to disk copy.

Page 42: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape Backup

• Large amounts of data historically favored tape media for backup:– Tapes are portable and fairly durable.

Page 43: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tapes

• Tape historically has been the preferred backup media for very large data storage environments.

• Tape has a useful life span.

• Tape can be very robust for storage

• Easy to transport

• Some tape formats are more reliable than others.

Page 44: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape Inventory

• Backup tapes must be – Properly labeled– Properly stored

• Proper inventory is needed to do restores in a timely fashion.– Hand written labels are ok– Bar codes and printed labels are better.

Page 45: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape Inventory

• Inventory is not limited to the physical tape itself.

• The contents of tapes must be inventoried.

• The number of accesses must be logged because tapes ware out.

– Tape equipment is not free. You don’t want to purchase any more hardware than is needed.

Page 46: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape

• Rotate media– Incremental backup stored on site can be

reused.

Page 47: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape Standards

• 8mm

• DLT

• DAT (4mm)

• QIC

• http://www.pctechguide.com/15tape.htm

• Imation.com

Page 48: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Tape Technology

• Tape technology expands in leaps.

• Tape hardware purchases are not made on a constant basis (like disk storage).

• Tape technology is purchased in leaps. Three year intervals are more practical.

Page 49: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Firedrills

• An occasional test of a full partition restore is not unreasonable. This would be done if– A change is made in the backup software

release.– A change of vendor for the backup software

product.– When a new server with new unused disk

arrives.

Page 50: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Centralization

• Without centralization, a tape drive is needed for each server location.

• Equipment can be interchanged more easily when centralized.

Page 51: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

High Access DB Backups

• Some data changes so rapidly that backups are not practical.

• RAID 1 mirroring may be the only practical solution.

• RAID 1+1, includes a second mirror in a RAID 1 array.

Page 52: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Technology

• Disk space cost drops by 1/2 about every 18-24 months.

• Disk space is filled as it expands.

• Disk requirements are increasing on a continuous basis.

• Disk budgets increase faster than tape backup budgets.

Page 53: Backup & Restore The purpose of backup is to protect data from loss. The purpose of restore is to recover data that is temporarily unavailable due to some.

Backup Procedure

• Choose your application

• Scheduling (know your data)

• The actual backup

• Inventory (content and media)

• Verify

• Automate

• Secure