SPARCstorage Array Configuration Guide
`
` A
`
` Sun Microsystems, Inc. Business
`2550 Garcia Avenue
`Mountain View, CA 94043 U.S.A.
`415 960-1300 FAX 415 969-9131
`Part No.: 802-2041-10
`Revision A, March 1995
`
`CISCO et al. v. CROSSROADS
`CQ-1008
`Page 1 of 30
`
`

`

` 1995 Sun Microsystems, Inc.
`2550 Garcia Avenue, Mountain View, California 94043-1100 U.S.A.
`
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`
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`The product described in this manual may be protected by one or more U.S. patents, foreign patents, or pending applications.
`
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`Recycle
`
`CQ-1008 / Page 2 of 30
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`

`Contents
`
`1. Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`1.1 SPARCstorage Array Model 100 System Features . . . . . .
`
`1.2 SPARCstorage Array Model 200 System Features . . . . . .
`
`1-1
`
`1-1
`
`1-3
`
`1.3 General Information for SPARCstorage Array Model 100 and
`200 Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`1-4
`
`2. Hardware Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2.1 Option 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2.2 Option 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2.3 Option 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2.4 Option 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`3. Software Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`3.1 Independent Disks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`3.2 Striping (RAID 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`3.3 Mirroring (RAID 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`3.4 Mirroring Striped Disks (RAID 0 + 1) . . . . . . . . . . . . . . . .
`
`3.5 RAID 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2-1
`
`2-2
`
`2-3
`
`2-4
`
`2-5
`
`3-1
`
`3-2
`
`3-2
`
`3-3
`
`3-4
`
`3-5
`
`iii
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`CQ-1008 / Page 3 of 30
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`

`

`3.6 Determining Which RAID Level to Use . . . . . . . . . . . . . .
`
`3.7 Other Facts on RAID and the SPARCstorage Array . . . .
`
`3-6
`
`3-7
`
`iv
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`SPARCstorage Array Configuration Guide—March 1995
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`CQ-1008 / Page 4 of 30
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`

`

`Figures
`
`Figure 1-1
`
`SPARCstorage Array Model 100 Series . . . . . . . . . . . . . . . . . . .
`
`Figure 1-2
`
`Internal Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 1-3
`
`SPARCstorage Array Model 200 Series Subsystem . . . . . . . . .
`
`Figure 2-1
`
`Option 1 Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 2-2
`
`Option 2 Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 2-3
`
`Option 3 Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 2-4
`
`Option 4 Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 3-1
`
`Example of Striped Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 3-2
`
`Example of Mirrored Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 3-3
`
`Example of Mirroring Striped Data . . . . . . . . . . . . . . . . . . . . . .
`
`Figure 3-4
`
`Graphical Representation of RAID 5 Writes . . . . . . . . . . . . . . .
`
`1-1
`
`1-2
`
`1-3
`
`2-2
`
`2-3
`
`2-4
`
`2-5
`
`3-2
`
`3-3
`
`3-4
`
`3-6
`
`v
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`CQ-1008 / Page 5 of 30
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`

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`vi
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`SPARCstorage Array Configuration Guide—March 1995
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`CQ-1008 / Page 6 of 30
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`

`

`Tables
`
`Table 2-1
`
`Option 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Table 2-2
`
`Option 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Table 2-3
`
`Option 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Table 2-4
`
`Option 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`Table 3-1
`
`Comparisons of RAID Levels . . . . . . . . . . . . . . . . . . . . . . . . . . .
`
`2-2
`
`2-3
`
`2-4
`
`2-5
`
`3-7
`
`vii
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`CQ-1008 / Page 7 of 30
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`viii
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`SPARCstorage Array Configuration Guide—March 1995
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`CQ-1008 / Page 8 of 30
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`

`

`Product Description
`
`1
`
`1.1 SPARCstorage Array Model 100 System Features
`The SPARCstorage™ Array Model 100 Series provides SCSI disk expansion for
`SPARCstation™, SPARCserver™ and SPARCcenter™ systems. It features three
`drive trays—each tray configured with up to ten half-height, single-connector,
`3.5-inch disk drives.
`
`The SPARCstorage Array Model 100 Series, shown in Figure 1-1, features front
`and rear component accessibility.
`
`Figure 1-1
`
`SPARCstorage Array Model 100 Series
`
`1-1
`
`CQ-1008 / Page 9 of 30
`
`

`

`Internal system components (see Figure 1-2) are:
`• Power supply
`• Backplane
`• Array controller, with
`• Fibre Channel Optical Module (FC/OM)
`• Battery module
`• Fan tray
`• Drive trays (3)
`
`1
`
`Fan tray
`
`Array controller
`
`Power supply
`
`Backplane
`
`Drive tray
`
`Figure 1-2
`
`Internal Components
`
`1-2
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 10 of 30
`
`

`

`1.2 SPARCstorage Array Model 200 System Features
`The SPARCstorage Array Model 200 Series is a rackmount disk array
`controller. Up to six Differential SCSI disk trays may be connected to it. See
`Figure 1-3.
`
`1
`
`Fan tray
`
`Power supply
`
`Diagnostic
`module
`
`Controller
`
`Differential
`SCSI interface
`
`Figure 1-3
`
`SPARCstorage Array Model 200 Series Subsystem
`
`Product Description
`
`1-3
`
`CQ-1008 / Page 11 of 30
`
`

`

`1
`
`Functional parts of the SPARCstorage Array Model 200 Series hardware
`include:
`• Removable power supply
`• Removable LCD-display diagnostic module
`• Removable disk array controller module
`• Removable Differential SCSI interface modules (two) with three differential
`SCSI ports per module
`• Removable fan tray
`• Internal backplane with attached power and signal buses
`• Rack-mountable chassis
`
`1.3 General Information for SPARCstorage Array Model 100 and 200 Systems
`The SPARCstorage Array connects to a host system using fibre optic cables.
`These cables connect to a Fibre Channel Optical Module (FC/OM) mounted on
`a Fibre Channel SBus (FC/S) card on the host system side, and to an FC/OM
`mounted on the array controller on the SPARCstorage Array side.
`
`You can have a maximum of two FC/OMs per FC/S card on the host system
`side and two FC/OMs on the array controller on the SPARCstorage Array side.
`Because of the number of FC/OMs available on both the host system and the
`SPARCstorage Array sides, you have several hardware configuration options
`when connecting a SPARCstorage Array to a server. Chapter 2, “Hardware
`Configurations,” contains all the information for you to choose the hardware
`configuration that best suits your needs.
`
`The SPARCstorage Array also has storage management software which offers
`several software options. Chapter 3, “Software Configurations,” contains all the
`information for you to choose the software configuration that best suits your
`needs.
`
`1-4
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 12 of 30
`
`

`

`Hardware Configurations
`
`2
`
`You have several options when it comes to connecting a SPARCstorage Array
`to a host system. The two factors that determine which options you should
`select are:
`• The number of SPARCstorage Arrays in the configuration
`• The number of host systems in the configuration
`
`When reviewing the following options, keep in mind that every SPARCstorage
`Array comes standard with one FC/OM and one fibre optic cable and that
`every FC/S card comes standard with one FC/OM.
`
`2-1
`
`CQ-1008 / Page 13 of 30
`
`

`

`2
`
`2.1 Option 1
`
`Table 2-1 Option 1
`
`Option
`
`Hardware Needed
`
`Notes
`
`One SPARCstorage Array on a single
`host SBus slot
`
`Order:
`- One SPARCstorage Array
`- One FC/S card
`
`Simplest, most common configuration
`
`Figure 2-1 shows how you would connect the SPARCstorage Array to a host
`system using this option.
`
`SPARCstorage Array
`
`Host System
`
`FC/OM
`
`FC/OM
`
`FC/S
`
`Figure 2-1 Option 1 Connection
`
`2-2
`
`SPARCstorage Array Configuration Guide—March 1995
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`CQ-1008 / Page 14 of 30
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`

`

`2
`
`2.2 Option 2
`
`Table 2-2 Option 2
`
`Option
`
`Hardware Needed
`
`Notes
`
`Two SPARCstorage Arrays on a
`single host SBus slot
`
`Order:
`- Two SPARCstorage Arrays
`- One FC/S card
`- One FC/OM
`
`- Highest capacity per SBus slot
`
`- Connecting 2 arrays on one SBus slot
`could possibly cause the FC/S to be a
`performance bottleneck on extremely
`demanding sequential I/O
`applications
`
`- Lower cost than using 2 FC/S cards
`for two arrays
`
`Figure 2-2 shows how you would connect the SPARCstorage Arrays to a host
`system using this option.
`
`SPARCstorage Arrays
`
`Host System
`
`FC/OM
`
`FC/OM
`
`FC/OM
`
`FC/S
`
`FC/OM
`
`Figure 2-2 Option 2 Connection
`
`Hardware Configurations
`
`2-3
`
`CQ-1008 / Page 15 of 30
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`

`

`2
`
`2.3 Option 3
`
`Option
`
`Hardware Needed
`
`Notes
`
`Table 2-3 Option 3
`
`Dual-host connection to
`a single SPARCstorage
`Array
`
`Order:
`- One SPARCstorage
`Array
`- Two FC/S cards
`- One FC/OM
`- One fibre optic cable
`
`Two possible reasons for this configuration:
`- Static dual-porting. Two systems connect to an array, but each
`disk in the array is “owned” by only one system at a time. One
`host system functions as a backup for the other host. * †
`
`- Sharing an array between two systems. Each system uses the
`reserve command to reserve a subset of the disks so that the
`other system is not allowed to access them. †
`
`*. Software to control and manage this type of high availability is not supplied with the SPARCstorage Array and must be purchased separately.
`†. Dual host configurations are potentially dangerous and can result in data corruption if both systems access the same disk at the same time.
`
`Figure 2-3 shows how you would connect the SPARCstorage Array to the host
`systems using this option.
`
`SPARCstorage Array
`
`FC/OM
`
`FC/OM
`
`Host Systems
`
`FC/OM
`
`FC/S
`
`FC/OM
`
`FC/S
`
`Figure 2-3 Option 3 Connection
`
`2-4
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 16 of 30
`
`

`

`2
`
`2.4 Option 4
`
`Option
`
`Hardware Needed
`
`Notes
`
`Table 2-4 Option 4
`
`Fully redundant, dual-
`hosted SPARCstorage
`Array
`
`Order:
`- Two SPARCstorage
`Arrays
`- Four FC/S cards
`- Two FC/OMs
`- Two fibre optic cables
`
`- This configuration is for the highest levels of availability where
`all hardware components are redundant.
`
`- When each array is set up so that it holds a complete copy of the
`data for both host system A and host system B, then any
`component in either array can fail with no loss of data service to
`the host systems * †
`
`*. Software to control and manage this type of high availability is not supplied with the SPARCstorage Array and must be purchased separately.
`†. Dual host configurations are potentially dangerous and can result in data corruption if both systems access the same disk at the same time.
`
`Figure 2-4 shows how you would connect the SPARCstorage Arrays to the host
`systems using this option.
`
`SPARCstorage Array A
`
`Data A
`
`FC/OM
`
`Data B, Mirrored
`
`FC/OM
`
`SPARCstorage Array B
`
`Data A, Mirrored
`
`Data B
`
`FC/OM
`
`FC/OM
`
`Figure 2-4 Option 4 Connection
`
`Host System A
`
`FC/OM
`
`FC/S
`
`FC/OM
`
`FC/S
`
`Host System B
`
`FC/OM
`
`FC/S
`
`FC/OM
`
`FC/S
`
`Hardware Configurations
`
`2-5
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`CQ-1008 / Page 17 of 30
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`

`

`2
`
`2-6
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`SPARCstorage Array Configuration Guide—March 1995
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`CQ-1008 / Page 18 of 30
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`

`

`Software Configurations
`
`3
`
`The SPARCstorage Volume Manager software can be configured for different
`levels of RAID, which stands for Redundant Array of Independent Disks.
`RAID is defined as a disk array in which part of the storage capacity is used to
`hold redundant information about user data that is stored on the remainder of
`the disk space capacity. The redundant information enables the user data to be
`regenerated if one of the array’s member disks or the access path to it fails.
`
`Following are the data layouts offered by the SPARCstorage Volume Manager
`storage management software:
`• Independent disks
`• RAID Level 0 (also known as striping)
`• RAID Level 1 (also known as mirroring)
`• RAID Level 0 + 1 (also known as mirroring striped disks)
`• RAID Level 5
`
`Note that the SPARCstorage Volume Manager storage management software
`allows all these data layouts to be mixed at the same time within the same
`array, with no restrictions on how the layouts are mixed and matched. These
`data layouts may be spread across multiple SPARCstorage Arrays. This
`flexibility allows you to configure your SPARCstorage Arrays to meet your
`specific requirements.
`
`These data layouts are explained in greater detail in the following sections.
`
`3-1
`
`CQ-1008 / Page 19 of 30
`
`

`

`3
`
`3.1 Independent Disks
`A data layout using independent disks has the following characteristics:
`• Best for most applications
`• No redundant data protection
`• Lowest cost per usable Mbyte
`
`3.2 Striping (RAID 0)
`Striping data spreads the data out over more than one physical disk so that the
`data is laid out evenly across the disks.
`
`If you were striping data over three physical disks, the first block of data
`would go on the first disk, the second block would go on the second disk, and
`the third block would go on the third disk. The fourth block of data would
`then go back on the first disk, the fifth block would go on the second disk, and
`so on. Figure 3-1 shows how data is spread out over three disks by striping the
`data.
`
`Physical disks
`
`B = Blocks of data
`
` B1
`
` B2
`
` B3
`
` B4
`
` B5
`
` B6
`
` B1 B4
`
`c1t0d0s1
`
`c1t0d0
`
` B2 B5
`
` B3 B6
`
`c2t0d0s1
`
`c2t0d0
`
`Figure 3-1
`
`Example of Striped Data
`
`3-2
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 20 of 30
`
`

`

`3
`
`A data layout using striping has the following characteristics:
`• Spreads data across multiple disk spindles for better performance
`• Can be tuned to optimize either random or sequential I/O performance
`• No redundant data protection, lower reliability than independent disks
`• Same low cost per usable Mbyte as independent disks
`
`3.3 Mirroring (RAID 1)
`Mirroring data copies the same data onto two or more separate physical disk
`drives. This is useful if you want to make sure data is available even if one
`physical disk fails; the data can be retrieved from the other physical disk that
`has the copy of the original data. In addition, it can sometimes improve read
`performance on busy data sets.
`
`If you were mirroring data to two physical disks, you would send the same
`data to both disks. Figure 3-2 shows how data would be mirrored to two
`physical disks.
`
`Physical disks
`
`B = Blocks of data
`
` B1 B2 B3
`
` B1
`
` B2
`
` B3
`
`c1t0d0s1
`
`c1t0d0
`
` B1 B2 B3
`
`Figure 3-2
`
`Example of Mirrored Data
`
`A data layout using mirroring has the following characteristics:
`• Duplicate copies of data, so if a disk fails, data is still available and
`applications keep running
`• Performance roughly the same as independent disks
`• Highest cost per usable Mbyte
`
`Software Configurations
`
`3-3
`
`CQ-1008 / Page 21 of 30
`
`

`

`3
`
`3.4 Mirroring Striped Disks (RAID 0 + 1)
`Mirroring striped disks consists of two separate operations:
`
`1. Data is striped across several physical disks.
`
`2. The data from the striped disks is mirrored on separate physical disks.
`
`This is useful if you want to get data written to or read from physical disks
`quickly and also want to make sure that data is available even if a disk fails.
`
`Figure 3-3 shows how you would stripe and mirror data over four physical
`disks.
`
`Physical disks
`
`B = Blocks of data
`
` B1
`
` B2
`
` B3
`
` B4
`
` B1 B3
`
`Striping
`
` B2 B4
`
`Mirroring
`
`c1t0d0s1
`
`c1t0d0
`
`c2t0d0s1
`
`c2t0d0
`
`c3t0d0s1
`
`c3t0d0
`
` B1 B3
`
` B2 B4
`
`Figure 3-3
`
`Example of Mirroring Striped Data
`
`3-4
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 22 of 30
`
`

`

`3.5 RAID 5
`
`3
`
`A data layout using mirroring striped disks has the following characteristics:
`• Duplicated copies of striped data remain available even if a disk fails
`• Combines performance of striping with data protection of mirroring
`• Has cost per usable Mbyte disadvantages of mirroring
`
`A RAID 5 configuration is similar to a striped configuration in that data is
`spread out evenly across several disks in a system. However, a RAID 5
`configuration adds a parity block to the stripe to provide redundancy. This
`parity block contains the result of an exclusive OR (XOR) procedure done on
`the data in the data stripes. If the data on one of the disks in the RAID 5
`configuration becomes inaccessible due to a hardware or software failure, data
`can be restored by XORing the contents of the remaining data disks with the
`parity disk. The data on the failed disk can be rebuilt from the output of the
`XOR process.
`
`When a write is performed on disks set up in a RAID 5 configuration, the data
`is written to all but one of the disks; the remaining disk then gets the parity
`information written to it. The next write performed on the disks in a RAID 5
`configuration would work the same way, except that the parity information
`would be written to a different disk than that used in the first write. That way,
`the parity information gets spread across all the disks in the configuration, so
`that if one disk fails, the data from that disks can be restored using the parity
`information written on the remaining disks in the configuration.
`
`For example, if three disks were used in a RAID 5 configuration, data written
`to those disks in this manner: for the first set of writes, data would be written
`to the first two disks in the configuration and the parity information would be
`written to the third disk. On the second set of writes to the disks, the data
`would be written to the first and third disks, and the parity information would
`be written to the second. On the third set of writes, the data would be written
`to the second and third disks, and the parity information would be written to
`the first. The fourth write would be performed as the first write was, with data
`on the first and second disks and parity information on the third. Figure 3-4
`shows how RAID 5 information would be written to disks using this setup.
`
`Software Configurations
`
`3-5
`
`CQ-1008 / Page 23 of 30
`
`

`

`3
`
`P
`
`PDD
`
`D
`
`DDP
`
`D
`
`DPD
`
`D = Data Stripe Unit
`P = Parity Stripe Unit
`
`Figure 3-4 Graphical Representation of RAID 5 Writes
`
`A data layout using RAID 5 has the following characteristics:
`• Spreads data across multiple disk spindles for better performance
`• Data remains available even if a disk fails because of parity
`• Slightly higher cost per usable Mbyte as independent disks or striping
`
`3.6 Determining Which RAID Level to Use
`The different RAID levels have varying degrees of benefits and liabilities in
`each of the following areas:
`• Cost — number of disks required
`• Data reliability — ability to get data even if disk fails
`• Data transfer capacity — ability to move large amounts of sequential access
`data rapidly
`• I/O rate — ability to satisfy large numbers of random I/O requests per unit
`time
`
`3-6
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 24 of 30
`
`

`

`3
`
`Refer to Table 3-1 for to determine which RAID level best suits your needs.
`
`Table 3-1 Comparisons of RAID Levels
`
` — much better than single disk
`¸ — slightly better than single disk
`
` — equal to single disk
`
`Data transfer capacity
`
` — slightly worse than single disk
`˛ — much worse than single disk
`I/O Rate
`
`RAID
`Levels
`
`0
`
`1
`
`0 + 1
`
`5
`
`Data
`Write
`Reading Data
`Writing Data
`Reliability
`Cost
`(cid:204) ˛ ˚ ˚ ˚ ˚
`
`Read
`
`˛ ˚ ˝
`
`¸
`
`¸
`
`˛ ˚ ˚ ˚ ˚ ˚
`
`˝ ˚ ˚ ˚ ˚ ˚
`
`3.7 Other Facts on RAID and the SPARCstorage Array
`• You can use any combination of independent disks or disks using RAID
`levels 0, 1, 0 + 1, or 5 in the same array.
`• RAID groups may even span multiple arrays.
`• Optional hot spares are automatically swapped in to replace any failed disk
`in a RAID 0 + 1 or 1 group without human intervention. Hot spares are
`extra disk drives in the array that are powered up and ready to use. If a
`drive in a RAID 0 + 1 or 1 group fails, the Volume Manager detects the
`failure and automatically rebuilds the data from the failed drive onto a hot
`spare drive.
`• There can be one or more hot spares per array. A hot spare drive can be tied
`to one or more particular drives, one or more particular RAID groups, or
`may be designated as a spare for any drive in any RAID group.
`• The combination of hot spares with warm pluggability provides new levels
`of high availability and administrative flexibility. Hot spares allow
`maintenance to be deferred for long periods of time and warm pluggability
`means that the array downtime is very short when a failed drive is
`eventually changed.
`• Since RAID is not ideal for many situations, the SPARCstorage Array allows
`you to configure disk drives as regular, independent disks, rather than
`forcing you to use RAID.
`
`Software Configurations
`
`3-7
`
`CQ-1008 / Page 25 of 30
`
`˚
`(cid:204)
`˝
`˝
`

`

`3
`
`• RAID stripe sizes are adjustable to optimize for either random or sequential
`I/O patterns.
`• Striped data organizations (RAID 0, 0 + 1 and 5) can be tuned to optimize
`for either random or sequential I/O performance.
`• To optimize for random performance, striping is used to evenly balance the
`I/O load across disk spindles in the RAID. This is done by setting the stripe
`width as large or larger than the typical application I/O request. For
`example, if the typical I/O request is 8 Kbytes, setting the stripe width to
`64 Kbytes might be appropriate. This tends to evenly distribute I/O request
`across all the disk drives in the RAID, and each I/O request is serviced by a
`single disk drive.
`• Sequential performance is optimized when data is spread out so that each
`application I/O request spans all the drives in the RAID group. This
`requires setting the stripe width so that it is small relative to the size of the
`typical I/O request. For example, in a RAID group four data disks wide, if
`typical application I/O size is 8 to 16 Kbytes, a stripe width of 2 Kbytes may
`be best.
`
`3-8
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 26 of 30
`
`

`

`H h
`
`ardware configurations
`considerations, 2-1
`for single host SBus slot, 2-2, 2-3
`for single host system, 2-2, 2-3
`for single SPARCstorage Array, 2-2,
`2-4
`for two host systems, 2-4, 2-5
`for two SPARCstorage Arrays, 2-3, 2-
`5
`full redundancy, 2-5
`highest capacity per SBus slot, 2-3
`sharing one array between two
`hosts, 2-4
`simplest, most common, 2-2
`static dual-porting, 2-4
`hot spares, 3-7
`
`M m
`
`irroring striped disks, see RAID level 0 +
`1
`mirroring, see RAID level 1
`
`P p
`
`arity, 3-5
`power supply, location, 1-2
`
`Index-1
`
`Index
`
`A a
`
`rray controller, location, 1-2
`
`B b
`
`ackplane, location, 1-2
`battery module, location, 1-2
`
`D d
`
`rive trays, location, 1-2
`
`F f
`
`an tray, location, 1-2
`FC/OM, see Fibre Channel Optical
`Module
`FC/S, see Fibre Channel Sbus card
`Fibre Channel Optical Module
`location, 1-2
`maximum number per FC/S, 1-4
`maximum number per SPARCstorage
`Array, 1-4
`Fibre Channel SBus card, standard
`package, 2-1
`
`CQ-1008 / Page 27 of 30
`
`

`

`R R
`
`AID
`considerations
`cost, 3-6
`data reliability, 3-6
`data transfer capacity, 3-6
`I/O rate, 3-6
`definition, 3-1
`determining which level to use, 3-6
`level 0 + 1, description, 3-4
`level 0, description, 3-2
`level 1, description, 3-3
`level 5, description, 3-5
`Redundant Array of Independent Disks,
`see RAID
`
`S S
`
`PARCstorage Array
`internal components, 1-2
`product description, 1-1
`standard package, 2-1
`striping, see RAID level 0
`
`W w
`
`arm pluggability, 3-7
`
`X X
`
`OR, 3-5
`
`Index-2
`
`SPARCstorage Array Configuration Guide—March 1995
`
`CQ-1008 / Page 28 of 30
`
`

`

`Reader Comments
`
`We welcome your comments and suggestions to help improve this manual. Please let us
`know what you think about the SPARCstorage Array Configuration Guide, part number
`802-2041-10.
`
`n The procedures were well documented.
`Strongly
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`q q q q q
`
`Not
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`Comments
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`n The tasks were easy to follow.
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`n The illustrations were clear.
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`Comments
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`n The information was complete and easy to find.
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`q q q q q
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`Not
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`Comments
`
`n Do you have additional comments about the SPARCstorage Array Configuration
`Guide?
`
`Name:
`
`Title:
`
`Company:
`
`Address:
`
`Telephone:
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`Email address:
`
`CQ-1008 / Page 29 of 30
`
`

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`CQ-1008 / Page 30 of 30
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`