Autoconfigure Storage Subsystem

This command automatically configures a storage subsystem. Before you enter the autoConfigure storageSubsystem command, run the show storageSubsystem autoConfiguration command. The show storageSubsystem autoConfiguration command returns configuration information in the form of a list of valid disk drive types, RAID levels, logical drive information, and hot spare information. (This list corresponds to the parameters for the autoConfigure storageSubsystem command.) The controllers audit the storage subsystem and then determine the highest RAID level that the storage subsystem can support and the most efficient logical drive definition for the RAID level. If the configuration that is described by the returned list is acceptable, you can enter the autoConfigure storageSubsystem command without any parameters. If you want to modify the configuration, you can change the parameters to meet your configuration requirements. You can change a single parameter or all of the parameters. After you enter the autoConfigure storageSubsystem command, the controllers set up the storage subsystem by using either the default parameters or those you selected.

Syntax

autoConfigure storageSubsystem [driveType=(fibre | SATA | SAS | PATA) raidLevel=(0 | 1 | 3 | 5 | 6) arrayWidth=numberOfDrives arrayCount=numberOfArrays logicalDrivesPerGroupCount=numberOfLogicalDrivesPerGroup hotSpareCount=numberOfHotSpares segmentSize=segmentSizeValue cacheReadPrefetch=(TRUE | FALSE) securityType=(none | capable | enabled)]

Parameters
Parameter Description

driveType

The type of disk drives that you want to use for the storage subsystem. Valid disk drive types are fibre, SATA, SAS, or PATA. The driveType parameter is not required if only one type of disk drive is in the storage subsystem.

raidLevel

The RAID level of the array that contains the disk drives in the storage subsystem. Valid RAID levels are 0, 1, 3, 5, or 6.

arrayWidth

The number of disk drives in an array in the storage subsystem.

arrayCount

The number of arrays in the storage subsystem. Use integer values.

logicalDrivesPerGroupCount

The number of equal-capacity logical drives per array. Use integer values.

hotSpareCount

The number of hot spares that you want in the storage subsystem. Use integer values.

segmentSize

The amount of data (in KB) that the controller writes on a single disk drive in a logical drive before writing data on the next disk drive. Valid values are 8, 16, 32, 64, 128, 256, or 512.

cacheReadPrefetch

The setting to turn on or turn off cache read prefetch. To turn off cache read prefetch, set this parameter to FALSE. To turn on cache read prefetch, set this parameter to TRUE.

securityType

The setting to specify the security level when creating the arrays and all associated logical drives. These settings are valid:

  • none ‑ The array and logical drives are not secure.
  • capable ‑ The array and logical drives are capable of having security set, but security has not been enabled.
  • enabled ‑ The array and logical drives have security enabled.
Notes
Disk Drives

An array is a set of disk drives that are logically grouped together by the controllers in the storage subsystem. The number of disk drives in an array is a limitation of the controller firmware. It is recommended that you adhere to the 30-disk drive limit and to the 2-TB size maximum for the array, which is imposed by some operating systems. This table relates disk drive capacity to the number of disk drives in an array.

Disk Drive Size Maximum Number of Disk Drives in the Array
18 GB 30 disk drives
36 GB 30 disk drives
73 GB 28 disk drives
180 GB 11 disk drives

A 73-GB disk drive or a 180-GB disk drive does not report exactly 73 GB or 180 GB as its capacity.

Hot Spares

Hot spare disk drives can replace any failed disk drive in the storage subsystem. The hot spare must be the same type of disk drive as the disk drive that failed (that is, a SATA hot spare cannot replace a Fibre Channel disk drive). A hot spare must have capacity greater than or equal to any disk drive that can fail. If a hot spare is smaller than a failed disk drive, you cannot use the hot spare to rebuild the data from the failed disk drive. Hot spares are available only for RAID Level 1, RAID Level 3, RAID Level 5, or RAID Level 6.

Segment Size

The size of a segment determines how many data blocks that the controller writes on a single disk drive in a logical drive before writing data on the next disk drive. Each data block stores 512 bytes of data. A data block is the smallest unit of storage. The size of a segment determines how many data blocks that it contains. For example, an 8-KB segment holds 16 data blocks. A 64-KB segment holds 128 data blocks.

When you enter a value for the segment size, the value is checked against the supported values that are provided by the controller at run time. If the value that you entered is not valid, the controller returns a list of valid values. Using a single disk drive for a single request leaves other disk drives available to simultaneously service other requests.

If the logical drive is in an environment where a single user is transferring large units of data (such as multimedia), performance is maximized when a single data transfer request is serviced with a single data stripe. (A data stripe is the segment size that is multiplied by the number of disk drives in the array that are used for data transfers.) In this case, multiple disk drives are used for the same request, but each disk drive is accessed only once. For optimal performance in a multiuser database or file system storage environment, set your segment size to minimize the number of disk drives that are required to satisfy a data transfer request.

Cache Read Prefetch

Cache read prefetch lets the controller copy additional data blocks into cache while the controller reads and copies data blocks that are requested by the host from the disk drive into cache. This action increases the chance that a future request for data can be fulfilled from cache. Cache read prefetch is important for multimedia applications that use sequential data transfers. The configuration settings for the storage subsystem that you use determine the number of additional data blocks that the controller reads into cache. Valid values for the cacheReadPrefetch parameter are TRUE or FALSE.

Security Type

The securityType parameter is valid for disk drives that are capable of Full Disk Encryption (FDE). With FDE, the controller firmware can create a key and activate the disk drive security feature. The disk drive security feature encrypts data as the data is written to the disk drive and decrypts the data as the data is read from the disk drive. Without the key created by the controller, the data written to the disk drive is inaccessible.

Before you can set the securityType parameter to capable or enabled, you must create a storage subsystem security key. Use the create storageSubsystem securityKey command to create a storage subsystem security key. These commands are related to the securtiy key:

Minimum Firmware Level

6.10

7.10 adds RAID Level 6 capability and removes hot spare limits.

7.50 adds the securityType parameter.