Ibm Disk Tech

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Copyright IBM Corp. 2011. All rights reserved. ibm.com/redbooks 1

Draft Document for Review August 20, 2011 6:15 pm 4791paper.fm

Redpaper

IBM System x Server Disk Drive

Technology

Introduction

In the server environments, disk storage is becoming more and more important, and the

choice of hard drives is very broad - connectivity intefaces (SAS, SATA) and their speeds,rotational speeds, desktop vs nearline vs enterprise drives, form-factors and so on. How to

choose the most appropriate HDD drive type?

The purpose of this document is to discuss currently available internal and external HDDstorage interfaces for IBM System x servers and to provide recommendations on how to

choose the right options to better fit business needs and application requirements. Thedocument is organized into the following sections:

Serial ATA (SATA) on page 1 Serial Attached SCSI (SAS) on page 3 Nearline (NL) disk drives on page 7 Application performance considerations on page 8 RAID on page 10 Drive selection guidelines on page 11

Serial ATA (SATA)

Serial ATA or Serial Advanced Technology Attachment (SATA) technology is a successor of

widely used Parallel ATA (PATA) or Enhanced IDE (EIDE) interface to attach different driveoptions including HDDs. SATA specifications are developed and maintained by Technical

Committee T13 - AT Attachment which is part of International Committee on InformationTechnology Standards (INCITS). Serial ATA International Organization (SATA-IO) has been

established in 2004 to promote and advance SATA connectivity technology worldwide. Themost recent SATA specification that has been adopted by the industry is Revision 3 thatfeatures 6 Gbps SATA connectivity along with the proven and widely used SATA Revision

1.0a with Serial ATA II extensions featuring 3 Gbps connection speed.

Ilia Kroutov
http://www.redbooks.ibm.com/http://www.redbooks.ibm.com/http://www.redbooks.ibm.com/http://www.redbooks.ibm.com/


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4791paper.fm Draft Document for Review August 20, 2011 6:15 pm

2 IBM System x Server Disk Drive Technology

The Serial ATA International Organization home page is:

http://www.sata-io.org

Intended use of the SATA interface in IBM System x servers is to provide internal low-cost

entry-level host connectivity for hard disk, optical, and tape drives. Typically, internal SATAconnectivity topology is based on two types of devices - SATA Initiator (SATA disk controller)

and SATA Targets (drives). SATA initiator and targets use the ATA command set tocommunicate with each other.

Entry-level IBM System x servers (such as the x3100 M3, x3200 M3, and x3250 M3) offer a

SATA HDD interface to provide low-cost internal storage solution. The SATA controller is builtinto the chipset on the system board. Some servers (like the x3100 M3) also have software

RAID assist capabilities as a feature of the integrated SATA controller. The maximum numberof drives supported is l imited by the number of physical ports on controller itself. Typical

internal SATA HDD connectivity topology is shown in Figure 1.

Figure 1 Entry-level IBM System x internal SATA HDD connectivity topology

SATA storage interface has the following characteristics:

Serial point-to-point connection architecture

Interface speeds of 1.5 Gbps, 3 Gbps, and 6 Gbps (150 MB/s, 300 MB/s, and 600 MB/s ofmaximum theoretical throughput respectively)

Single-port device connections (the port consists of one pair of links - transmit and

receive, and each link consists of two physical wires that use Low Voltage DifferentialSignalling)

Support for narrow ports only (no wide port or port link aggregation unlike SAS - refer tothe "Serial SAS" section for more information)

Half-duplex port operation

One target device per initiator's port Support for port multipliers with command-based or Frame Information Structure

(FIS)-based switching to connect more than one target to the same initiator's por t

Support for external SATA connectivity (eSATA)

No multi-initiator support (no shared storage clustering possible)

Cyclic redundancy check (CRC) for data integrity

Support for Native Command Queuing (NCQ) which allows to reorder disk data access

command sequence to optimize seek time by minimizing physical movement of magneticsheads over disk plate

SATA Controller

SATA HDDs

SATA ports

SATA links
http://www.sata-io.org/http://www.sata-io.org/


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IBM System x Server Disk Drive Technology3


Support for SATA devices only (SAS devices are not supported)

Support for hot-swap devices

Support for SATA backward compatibility

7-pin L-shape physical connector

The integrated SATA controller used in many IBM System x servers has the followingcharacteristics:

Interface speed of 3 Gbps (300 MB/s of maximum theoretical throughput)

Up to six internal SATA ports in entry servers and up to two SATA ports in midrange andhigh-end servers (typically, up to four ports are used to connect hard drives in entry

servers, and up to two ports are used to connect optical or tape drives in all servers)

One target device per port

Support for internal devices only

Support for Native Command Queuing (NCQ)

Support for simple-swap devices only1

IBM SATA hard disk drives have the following characteristics:

Interface speeds of 3 Gbps and 6 Gbps (300 MB/s and 600 MB/s of maximum theoretical

throughput respectively)

Rotational speed of 7.2K RPM

Single hard drive capacities of 250 GB, 500 GB, 1 TB, 2 TB, and 3 TB.

Support for Native Command Queuing (NCQ)

Support for S.M.A.R.T.

Lower power consumption compared to SAS drives

2.5" and 3.5" form-factor

Simple-swap and hot-swap HDDs

Traditional or Desktop SATA drives are intended for use in 8x5 hours of operation (8 hoursper day, 5 days per week) and low I/O single user desktop workload environments and do not

fit well into server environments. Because of that, IBM System x servers always useEnterprise SATA drives (also known asNearline orNL SATA drives) as they offer almosttwice better reliability, better support of multi-drive RAID array deployments, and 24x7 hoursof operation (24 hours per day, 7 days per week) in multi-user workload environments while

not bringing significant cost disadvantage compared to desktop SATA drives.

IBM SATA HDDs provide reliable and most energy- and cost per gigabyte-efficient storage forlightly-loaded departmental applications that store user data such as file servers and e-mail

servers, or for infrequent bandwidth-intensive sequential workloads such as archives,

imaging, multimedia libraries, and disk backups.

Serial Attached SCSI (SAS)

Serial Attached Small Computer System Interface or Serial Attached SCSI (SAS) connectivitytechnology is an evolution of parallel SCSI interface intended to overcome performance and

1 IBM System x servers support hot-swap SATA drives with SAS RAID controllers. See Serial Attached SCSI (SAS)

on page 3 for more information.


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scalability limitations of bus topology while providing enterprise-class reliability and softwarestack compatibility.

SAS specifications are developed and maintained by Technical Committee T10 - SCSIStorage Interfaces which is part of International Committee on Information Technology

Standards (INCITS). The SCSI Trade Association (STA) was established in 1996 to promoteand advance SCSI connectivity technology worldwide.

The SCSI Trade Associations web site is:

http://www.scsita.org

SAS was initially introduced in 2004 as a 3 Gbps connectivity technology (SAS-1). The most

recent SAS specification that has been adopted by the industry is Revision 2 (SAS-2) thatfeatures 6 Gbps SAS connectivity.

Because of its high performance, reliability, and scalability features, SAS interface is widely

used in the IBM System x server systems for both internal and external storage connectivityfor wide range of applications and usage patterns.

In general, there are three type of devices that form SAS topology:

SAS initiators SAS or SATA targets SAS expanders

The initiators are the SAS controllers (the IBM SAS RAID controllers or SAS Host BusAdapters - HBAs) and the targets are the end-point devices such as disk or tape drives. SAS

targets can be directly connected to the SAS initiator ports or indirectly through SASexpanders (or even sequence of SAS expanders).

Essentially, a SAS expander is a switch device that allows to connect more target devices tothe initiator than the number of ports the initiator has, therefore dramatically increasing SAS

fabric scalability without sacrificing reliability and performance. In addition, expanders support

wide SAS links (or aggregated links) that consist of several narrow SAS links forexpander-expander or expander-initiator connections to increase overall performance offabric.

A narrow SAS port is an interface that has one pair of transmit/receive links (the pair oftransmit/receive link is commonly referred as PHY), and a wide SAS port has more than onepair of transmit/receive links (up to eight) that represent one aggregated link with single World

Wide Name (WWN) address.

Each SAS device has a World Wide Name (WWN) address which is used to uniquely identifythis device in the SAS fabric. SAS expanders maintain the WWN address routing tables to

forward control and data traffic between the targets and initiators which is very similar totraditional network switch operations.

A SAS expander can be implemented as a separate I/O card installed in the PCI-E expansion

slot (like in the x3500 M3 or x3650 M3 servers when the number of drive bays is greater thaneight) or can be integrated into the disk backplane (like in the x3630 M3) or into the expansion

enclosure (like in the IBM System Storage DS2500 series external storage enclosures).

SAS specification defines three protocols used for communications between initiators,targets, and expanders:

Serial SCSI Protocol (SSP), which is used to communicate between initiators and SAStarget devices such as hard drives
http://www.scsita.org/http://www.scsita.org/


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Serial Management Protocol (SSP), which supports SAS expanders

Serial ATA Tunneled Protocol (STP), which supports attachment of SATA targets in SAS

fabric.

The following figures show most common SAS connectivity topologies used in IBM System xservers. In these figures, each physical SAS connector incorporates four SAS PHYs. Figure 2

shows how each SAS PHY can be a separate SAS port connected to an end-point devicesuch as a disk drive.

Figure 2 Typical internal SAS Connectivity without expanders

Figure 3 on page 5 shows how the four SAS PHYs can be combined into single x4 wide SASport connected to the SAS expander.

Figure 3 Typical internal SAS Connectivity with expanders

S AS RAID Controller

SAS or SATA HDDs

Physical SAS connectors

Narrow SAS links

HDD Backpl ane

SAS RAID Co ntrol ler

SAS or SATA HDDs

Physical SAS connectors

Narrow SAS links

HDD Backplanes

Wi de SAS l inks

SAS Expander


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External SAS connectivity can be extremely scalable as it allows SAS expanders to beconnected to each other, for example, single IBM ServeRAID M5025 RAID Controller can

handle up to 18 IBM System Storage DS2512 expansion enclosures serving up to 216 3.5"hard disk drives. Typical connectivity topology in this case is shown on Figure 4.

Figure 4 Typical external SAS connectivity with expanders

SAS storage interface has the following characteristics:

Serial point-to-point connection architecture

Connection-oriented data transmission

Interface speeds of 3 Gbps, and 6 Gbps (300 MB/s, and 600 MB/s of maximum theoreticalthroughput respectively)

Dual-port device connections (the port consists of one pair of transmit and receive links,and each link consists of two physical wires that use Low Voltage Differential Signalling)

Support for narrow and wide (aggregated) ports, aggregated wide port throughput up to2400 MB/s (four 6 Gbps PHYs or x4 link)

Full-duplex port operation

More than one target device per initiator's port with SAS expanders

SAS RAID Controller

S AS or SATAHDDs

HDDBackplane

Wide SAS links S ASExpander

DS2515ExpansionEnclosure


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Support for internal and external connectivity

Multi-initiator support

Zoning support

Cyclic redundancy check (CRC) for data integrity

Enterprise-level error recovery

Support for SAS and SATA devices

Support for hot-swap devices

Support for SAS and SATA backward compatibility

Physical connectors: SFF-8087 (internal) and SFF-8088 (external)

IBM offers broad range of IBM ServeRAID SAS RAID controllers for IBM System x servers

from entry-level to advanced to support both internal and external storage attachments .Refer to the following links for more information:

IBM ServeRAID H1110

http://www.redbooks.ibm.com/abstracts/tips0831.html?Open

IBM ServeRAID M1015


IBM ServeRAID M5014/M5015


IBM ServeRAID M5025


IBM SAS hard disk drives have the following characteristics:

Interface speeds of 3 Gbps and 6 Gbps (300 MB/s and 600 MB/s of maximum theoreticalthroughput respectively)

Rotational speed of 10K RPM and 15K RPM

Single hard drive capacities of 73 GB, 146 GB, 300 GB, 600 GB, and 900 GB.

Support for Tagged Command Queuing (TCQ) which allows to reorder disk data accesscommand sequence to optimize seek time by minimizing physical movement of magnetics

heads over disk plate

Support for Predictive Failure Analysis (PFA)

2.5" and 3.5" form-factor

Simple-swap and hot-swap HDDs

IBM SAS HDDs are designed for 24x7 hours of operations (24 hours per day, 7 days perweek) for continuous multi-user I/O-intensive workloads such as OLTP databases, data

warehouses, and heavily loaded file servers and e-mail servers. IBM SAS connectivityprovide high performance, high availability, and scalability for mission critical enterprise

applications, and establish a foundation for building multi-tiered storage architectures.

Nearline (NL) disk drives

The termNearline disk drive means that data stored on these drives are intended to beaccessed infrequently while require 24x7 availability at the same time. From the application
http://www.redbooks.ibm.com/abstracts/tips0831.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0740.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0738.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0739.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0739.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0738.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0740.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0831.html?Open


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perspective, these drives are commonly used for storing archives, document images,multimedia libraries, and backups. There are two types of nearline drives - NL SATA and NL

SAS. NL SATA is also commonly referred as anEnterprise SATA in the literature.

NL SATA drives use native SATA interface and have the same capacity and performance

characteristics as traditional or desktop SATA drives but have better reliability, tolerance tovibration, and designed for 24x7 hours of operation comparing to them. In general, reliabilityand tolerance to vibration of NL SATA drive is twice higher than those ones of traditional

SATA drive. Vibration tolerance is very important for deployment of multi-drive arrays such asRAID arrays to eliminate risk of read/write errors and retry cycles because of HDD rotational

vibration interference.

NL SAS has the same performance, capacity, and reliability characteristics as NL SATAdrives. The only difference is that NL SAS drives provide native SAS interface capabilitiesincluding dual-port connectivity, full-duplex data transfer, data integrity, and SCSI command

support.

Application performance considerations

In general, there are two key types of storage applications based on workload they generate:

I/O-intensiveapplications require storage system to process as many host's read andwrite requests (or I/O requests) per second as possible given the average request size

used by this application. This behavior is most common for OLTP databases and datawarehouses.

Throughput-intensiveapplications require storage system to transfer to or from host asmany gigabytes of information per second as possible. These characteristics commonly

inherent to file servers, multimedia streaming, and backup.

Therefore, there are two key performance metrics to evaluate the storage applicationperformance: input/output requests per second (IOPS)or throughput depending on

application's workload.

Other considerations to better plan storage deployment include how does the applicationaccess data - read-intensive or write-intensive, and random data access or sequential data

access. Table 1 summarizes typical application workload patterns depending on applicationtype.

Table 1 Typical application workload patterns

Workload Type

Application Type

Read

intensive

Write

intensive

I/O

intensive

Throughput

intensive

Random

access

Sequential

access

OLTP Database Yes Yes Yes Yes

Data warehouse Yes Yes Yes

File server Yes Yes Yes

E-mail server Yes Yes Yes Yes

Document imaging Yes Yes Yes

Multimedia Yes Yes Yes

Web/Internet Yes Yes Yes

CAD/CAM Yes Yes Yes


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As a general rule, to deploy most efficient storage that satisfies application performance

requirements given the required storage capacity, you should consider: A higher number of drives for I/O-intensive workloads (more drives of smaller capacities

as adding drives provides almost linear increase in IOPS)

A higher bandwidth between the host controller and storage arrays forthroughput-intensive workloads (utilizing more host ports on a controller and higher port

speeds (6 Gbps rather than 3 Gbps) with a sufficient number of drives in the array to putthe workload on these links.

Both the number of drives and the way the drives are connected to the controller determines

throughput as a perfromance metric:

Drives connected directly to the controller (typically 1-8 drives) Drives connected to the controller via a SAS expander (more than 8 drives)

To illustrate the difference, lets assume we have an array of eight HDDs, each drive iscapable of 200 MB/s of sustained throughput (which is, in fact, a best case scenario usingtodays HDD technology), and the host is reading 8 GB of data from this array evenly

distributed across all drives. As we discussed earlier, the thoughput means how quickly thelarge sequental amout of data can be transferred from drive to host or back.

If HDD array is formed from the drives directly connected to the ports on RAID controller (seeFigure 2 on page 5), then every drive has a point-to-point link between itself and RAIDcontroller, and this link has a bandwidth of 300 MB/s for 3 Gpbs SAS and 600 MB/s for 6

Gbps SAS interfaces. Because 200 MB/s of single drive throughput is less than either 300MB/s or 600 MB/s there is no difference between 3 Gbps or 6 Gbps interfaces as the link itself

is not the limiting factor. In any case eight drives can provide up to 1600 MB/s of throuhput

therefore tranferring 8 GB in 5 seconds using either 3 Gbps or 6 Gbps inteface. The use of a6 Gbps provides little performance improvement.

In case when HDDs are connected to the ports on a RAID controller through expanders likeshown on Figure 3 on page 5 or Figure 4 on page 6 the bandwidth of the link between RAID

controller and expander and the drive interface speed become very important.

Eight drives that work simultaneously can provide up to 1600 MB/s. 3 Gbps x4 SAS link canhandle up to 1200 MB/s, therefore the time to transfer 8 GB of data will be about 7 seconds,and the limiting factor is the link bandwidth. In case of 6 Gbps x4 SAS link which has 2400

MB/s of bandwidth, transfer time will be 5 seconds as the link will not be limiting factor. In thisinstance, the use of a 6 Gbps controller and drives will offer a significant performance gain

over 3 Gbps equivalent devices. If 3 Gbps HDDs will be used in this scenario, then becasue of

the way SAS manages conections and matches speeds of links between initiators andtargets, the effective bandwidth between controller and expander will not exceed 1200 MB/s,and transfer time will also be about 7 sec. Because of that, it is very important to match thespeeds of RAID controller ports and drive interfaces.

In summary:

When drives are directly connected to the controller, the drive performance is the limitingfactor

Backup Yes Yes Yes

Workload Type

Application Type

Read

intensive

Write

intensive

I/O

intensive

Throughput

intensive

Random

access

Sequential

access


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10 IBM System x Server Disk Dr ive Technology

When dirves are connected to the controller via a SAS expander, the link between theexpander and controller (6 Gbps or 3 Gbps) is the limiting factor, since the drives can fully

saturate the link

RAID

To increase performance and reliability of disk subsystem RAID arrays are commonly used.RAID array is a group of physical disks that uses certain common method to distribute data

across the disks. The data are distributed by stripe units. A stripe unit is the portion of datawritten to the one disk drive at once before the write operation continues on next drive. When

the last drive in array is reached the write operation continues on the first drive in the blockadjacent to the previous stripe unit written to this drive and so on.

The group of stripe units subsequently written to all drives in the array (from the first drive tothe last drive) before write operation continues on the first drive is called a stripe, and theprocess of distributing data is called striping. A stripe unit is a minimal element that can beread from or written to the RAID array, and stripe units may contain data or recovery

information.

The certain striping method used for data distribution is also known as the RAID level, and ithas certain level of availability, performance, and available storage capacity as achieving

redundancy is always at the expense of disk space reserved for storing recovery information.

There are basic RAID levels - 0, 1, 5, and 6, and spanned RAID levels - 00, 10, 50, 60.Spanned RAID arrays combine two ore more basic RAID arrays to provide higherperformance, capacity, and availability by overcoming limitation of the maximum number ofdrives per array supported by a particular RAID controller. For example, the IBM ServeRAID

M5014 and M5015 support up to 16 drives in a single (basic or spanned) array while theServeRAID M5025 supports up to 32 drives per basic array and one spanned array consisting

of up to eight basic arrays resulting in theoretical l imit of 256 devices.

Table 2 on page 10 and Table 3 on page 11 summarize the RAID levels and theircharacteristics. The following variables used in these tables:

K means number of drives in a single array

L means number of spans (the number of basic arrays that can be a part of singlespanned array)

N refers to a number of drives with respect to redundancy. For example N+1 means thearray can sustain one drive failure and still perform I/O operations.

When redundancy is listed as L*(N+x) that means the spanned array can sustain L*x drivefailures providing these failures happened in different basic arrays.

Table 2 Table 2. RAID levels - Basic arrays

RAID level

Characteristics

RAID 0 RAID 1 RAID 5 RAID 6

Striping method Striping Mirroring Striping with

distributed parity

Striping with dual

distributed parity

Minimum number of drives 1 2 3 4

Capacity (available space) K*(Single Drive

Size)

(Single Drive Size) (K-1)*(Single Drive

Size)

(K-2)*(Single Drive

Size)


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Table 3 Table 2. RAID levels - Spanned arrays

Drive selection guidelines

The most common criteria used to choose most appropriate storage solution for server

environments are based on the following: Application I/O workload pattern Cost Capacity Performance Scalability Reliability Power consumption Physical environment

Use NL SATA drives when:

Cost per GB is a key decision factor

Large single array capacity is required Infrequent sequential or light I/O workloads are planned

Use NL SAS drives when:

Cost per GB is a key decision factor Large single array capacity is required Reliability is important Infrequent sequential enterprise level I/O workloads are planned

Redundancy No N+N N+1 N+2

Read performance Excellent Very good Excellent Excellent

Write performance Excellent Very good Satisfactory Satisfactory

RAID level

Characteristics

RAID 0 RAID 1 RAID 5 RAID 6

RAID level

Characteristics

RAID 10 RAID 50 RAID 60

Striping method Spanned mirroring Spanned striping

with distributed

parity

Spanned striping

with dual

distributed parity

Minimum number of drives 4 6 8

Capacity (available space) L*(Single DriveSize)

L*(K-1)*(SingleDrive Size)

L*(K-2)*(SingleDrive Size)

Redundancy L*(N+N) L*(N+1) L*(N+2)

Read performance Very good Excellent Excellent

Write performance Very good Satisfactory Satisfactory


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Use 15K RPM SAS drives when:

Application performance and response time are extremely important Reliability is extremely important Continuous random enterprise level I/O workloads are planned

Use 10K RPM SAS drives when:

Application performance and response time are important Reliability is extremely important Continuous random enterprise level I/O workloads are planned

Use 2.5" drives when:

GB per U density is important Storage performance density (IOPS per U or throughput per U) is important Storage energy efficiency is important

Use 6 Gbps drives when:

6 Gbps controller is used Number of drives is more than 8 (when SAS expanders are used)

Sequential throughput-intensive workloads are planned

Because SAS fabric provides flexibility in support of both SAS and SATA devices, the SASand SATA drives can be intermixed in the same system or enclosure to better fit specific

application workloads being deployed on it. However, the mixing SAS and SATA requiresservers support, since there are thermal and vibration implications when mixing drive types.

For reference purposes, Table 4 provides summary of characteristics for different storageconnectivity types.

Table 4 Feature comparison by connectivity technology

Note: The termsLow,Moderate,High, and Very High used in the table below are relativeindicators for comparison purposes and do not represent any meaning in terms of absolutevalues. For example, values in the Reliability row mean that NL SATA and NL SAS drives

have better reliability than SATA drives, and SAS drives have better reliability than NL SASor NL SATA drives.

Disk drive

feature

SATA NL SATA NL SAS SAS

Interface speed 3 Gbps or 6 Gbps 3 Gbps or 6 Gbps 6 Gbps 6 Gbps

Interface

bandwidth

300 MB/s or 600 MB/s 300 MB/s or 600 MB/s 600 MB/s 600 MB/s

RPM 7.2K 7.2K 7.2K 10K or 15K

Drive port

connections

1 1 2 2

Duplex support Half-duplex Half-duplex Full-duplex Full-duplex

SATA Controller

support

Yes Yes No No

SAS Controller

support

Yes Yes Yes Yes


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For reference purposes, Table 5 lists hard disk drives currently available for IBM System x

servers.

Table 5 Supported hard disk drives

Hot-swap support Yes Yes Yes Yes

Multi-drive array

suitability

(tolerance tovibration)

Low High High Very High

24x7 targeted

power on hours

No Yes Yes Yes

24x7 targeted I/O

workloads

No No No Yes

Reliability Low High High Very High

Sequential

read/write

performance

High High High High

Randomread/write

performance

Low Low Low High

Power

consumption

Low Low Low Moderate

Drive Capacity High High High Moderate

Scalability Low Low High High

Cost Low Moderate Moderate High

Targeted

application

workloads

Single user desktop

applications such as

working with

documents and

e-mail, and browsing

web.

Lightly-loaded

departmental

applications storing

user data such as file

servers and e-mail

servers.

Infrequent

bandwidth-intensive

sequential workloads

that require reliable

storage such as

archives, imaging,

multimedia libraries,

and disk backups.

I/O intensive random

mission critical

workloads that require

continuous (24x7)

data access and fast

response time such as

OLTP databases, data

warehouses, and

heavily loaded file

servers and e-mail

servers.

Disk drive

feature

SATA NL SATA NL SAS SAS

Part number Description

3.5" Simple-Swap SATA HDDs

39M4508 250GB 7200 RPM 3.5" Simple-Swap SATA II

43W7750 IBM 250GB SATA 3.5'' SS HDD

39M4514 500GB 7200 RPM 3.5" Simple-Swap SATA II


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None* IBM Server 1TB 7200 SATA 3.5" Simple Swap HDD

42D0787 IBM 2TB 7200 NL SATA 3.5" SS HDD

3.5" Hot-Swap SATA HDD

39M4526 250GB 7200 RPM 3.5" Hot-Swap SATA II

43W7754 IBM 250GB SATA 3.5'' HS HDD

39M4530 500GB 7200 RPM 3.5" Hot-Swap SATA II

43W7626 IBM 1TB 7200 SATA 3.5" HS HDD

42D0782 IBM 2TB 7200 NL SATA 3.5" HS HDD

81Y9774 IBM 3TB 7.2K 6Gbps NL SATA 3.5'' HS HDD

3.5" Hot-Swap SAS HDDs

44W2234 IBM 300GB 15K 6Gbps SAS 3.5" Hot-Swap HDD



42D0777 IBM 1TB 7.2K 6Gbps NL SAS 3.5" HS HDD

42D0767 IBM 2TB 7.2K 6Gbps NL SAS 3.5" HS HDD

81Y9758 IBM 3TB 7.2K 6Gbps NL SAS 3.5'' HS HDD

2.5" Hot-Swap SAS HDDs

42D0672 IBM 73GB 15K 6Gbps SAS 2.5 SFF Slim-HS HDD

42D0632 IBM 146GB 10K 6Gbps SAS 2.5" SFF Slim-HS HDD


44W2294 IBM 146GB 15K 6Gbps SAS 2.5" SFF Slim-HS SED


44W2264 IBM 300GB 10K 6Gbps SAS 2.5" SFF Slim-HS SED

81Y9670 IBM 300 GB 15K 6Gbps SAS 2.5" SFF HS HDD

42D0707 IBM 500GB 7200 6Gbps NL SAS 2.5'' SFF Slim-HS HDD

49Y2003 IBM 600GB 10K 6Gbps SAS 2.5" SFF Slim-HS HDD

81Y9650 IBM 900 GB 10K 6Gbps SAS 2.5" HS HDD

81Y9690 IBM 1TB 7.2K 6Gbps NL SAS 2.5'' SFF Slim-HS HDD

2.5" Hot-Swap SATA HDDs

42D0747 IBM 160GB 7200 NL SATA 2.5'' SFF Slim-HS HDD

81Y9722 IBM 250GB 7.2K 6Gbps NL SATA 2.5'' SFF Slim-HS HDD

81Y9726 IBM 500GB 7.2K 6Gbps NL SATA 2.5'' SFF Slim-HS HDD

42D0752 IBM 500GB 7200 NL SATA 2.5'' SFF Slim-HS HDD

81Y9730 IBM 1TB 7.2K 6Gbps NL SATA 2.5'' SFF Slim-HS HDD



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Related publications

For more information refer to the following documents:

System x RAID products home page:

http://www.ibm.com/systems/storage/product/systemx/scsi_raid.html

IBM ServeRAID software matrix:

http://www.ibm.com/support/docview.wss?uid=psg1SERV-RAID

IBM System x Configuration and Options Guide:

http://www.ibm.com/support/docview.wss?uid=psg1SCOD-3ZVQ5W

IBM ServeRAID Quick Reference


IBM ServeRAID H1100 at-a-glance guide


IBM ServeRAID M1015 at-a-glance guide


IBM ServeRAID M5014/M5015 at-a-glance guide


IBM ServeRAID M5025 at-a-glance guide


Self-Encrypting Drives at-a-glance guide


The team who wrote this paper

This paper was produced by a team of specialists working at the International TechnicalSupport Organization, Raleigh Center.

Ilia Kroutov is an Advisory IT Specialist with IBM Russia and has been with IBM since 1998.

He is currently the Brand Manager for IBM System x and BladeCenter offerings for Russiaand CIS countries. Prior to this, he was a Field Technical Sales Support (FTSS) specialist for

System x products with a major focus on IBM BladeCenter, and an instructor at IBM LearningServices Russia, conducting training classes related to IBM Netfinity and System xhardware, Microsoft server operating systems, and Cisco networking equipment topics. He

has IBM Certified Advanced Technical Expert - IBM BladeCenter certification andcertifications from Cisco Systems (CCNP, CCSP, CCDA). He graduated from the Moscow

2.5" Hot-Swap SATA Solid state drives

43W7714 IBM 50 GB SATA 2.5" SFF Slim-HS High IOPS SSD

2.5" Simple-Swap SATA Solid state drives

None* 50 GB Simple Swap SATA SSD

http://www.ibm.com/systems/storage/product/systemx/scsi_raid.htmlhttp://www.ibm.com/support/docview.wss?uid=psg1SERV-RAIDhttp://www.ibm.com/support/docview.wss?uid=psg1SCOD-3ZVQ5Whttp://www.redbooks.ibm.com/abstracts/tips0054.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0831.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0740.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0738.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0739.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0761.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0761.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0739.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0738.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0740.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0831.html?Openhttp://www.redbooks.ibm.com/abstracts/tips0054.html?Openhttp://www.ibm.com/support/docview.wss?uid=psg1SCOD-3ZVQ5Whttp://www.ibm.com/support/docview.wss?uid=psg1SERV-RAIDhttp://www.ibm.com/systems/storage/product/systemx/scsi_raid.html


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Engineering and Physics Institute, and holds a Masters degree in Computer Engineering. Iliais an Accredited IT Specialist.

Thanks to the following people for their contributions to this project:

David Watts, IBM Redbooks Linda Robinson, IBM Redbooks

Scott Seal, IBM System x world-wide product marketing

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Copyright International Business Machines Corporation 2011. All rights reserved.

Note to U.S. Government Users Restricted Rights -- Use, duplication or disclosure restricted by

GSA ADP Schedule Contract with IBM Corp. 17

Draft Document for Review August 20, 2011 6:15 pm 4791paper-spec.fm

Notices

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Redpaper

This document REDP-4791-00 was created or updated on August 20, 2011.

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