Set Storage Subsystem

This command defines the properties of the storage subsystem.

Syntax

set storageSubsystem {alarm=(enable | disable | mute) | {autoSupportConfig (enable | disable) | cacheBlockSize=cacheBlockSizeValue | cacheFlushStart=cacheFlushStartSize | cacheFlushStop=cacheFlushStopSize | defaultHostType=(“hostTypeName” | hostTypeIdentifier) failoverAlertDelay=delayValue | mediaScanRate=(disabled | 1-30) | password=”password” | userLabel=”storageSubsystemName”}

Parameters
Parameter Description

alarm

The setting for the audible alarm. This parameter has these values:

  • enable – The audible alarm is turned on and sounds if a fault occurs.
  • disable – The audible alarm is turned off and does not sound if a fault occurs.
  • mute – The audible alarm is turned off if it is sounding.

If another fault occurs after you set the audible alarm to mute, the audible alarm sounds again.

autoSupportConfig

The setting for automatically collecting support data. This parameter has these values:

  • enable – Turns on the collection of support data
  • disable – Turns off the collection of support data

cacheBlockSize

The cache block size that is used by the controller for managing the cache. Valid values are 4 (4 KB), 8 (8 KB), 16 (16 KB), or 32 (32 KB).

cacheFlushStart

The percentage of unwritten data in the cache that causes a cache flush. Use integer values from 0 to 100 to define the percentage. The default value is 80.

cacheFlushStop

The percentage of unwritten data in the cache that stops a cache flush in progress. Use integer values from 0 to 100 to define the percentage. This value must be less than the value of the cacheFlushStart parameter.

defaultHostType

The default host type of any unconfigured HBA host port to which the controllers are connected. To generate a list of valid host types for the storage subsystem, run the show storageSubsystem hostTypeTable command. Host types are identified by a name or a numerical index. Enclose the host type name in double quotation marks (“ ”). Do not enclose the host type numerical identifier in double quotation marks.

failoverAlertDelay

The failover alert delay time in minutes. The valid values for the delay time are 0 to 60 minutes. The default value is 5.

mediaScanRate

The number of days over which the media scan runs. Valid values are disabled, which turns off the media scan, or 1 day to 30 days, where 1 day is the fastest scan rate, and 30 days is the slowest scan rate. A value other than disabled or 1 to 30 does not allow the media scan to function.

password

The password for the storage subsystem. Enclose the password in double quotation marks (“ ”).

userLabel

The name for the storage subsystem. Enclose the storage subsystem name in double quotation marks (“ ”).

Notes

When you use this command, you can specify one or more of the optional parameters.

Auto Support Data

When enabled, the set storageSubsystem autoSupportConfig command causes all configuration and state information for the storage subsystem to be returned each time a critical Major Event Log (MEL) event is detected. The configuration and state information is returned in the form of an object graph. The object graph contains all relevant logical and physical objects and their associated state information for the storage subsystem.

The set storageSubsystem autoSupportConfig command collects configuration and state information in this way:

You can run the set storageSubsystem autoSupportConfig command on more than one storage subsystem.

Cache Block Size

When you define cache block sizes, use the 4-KB cache block size for storage subsystems that require I/O streams that are typically small and random. Use the 8-KB cache block size when the majority of your I/O streams are larger than 4 KB but smaller than 8 KB. Use the 16-KB cache block size or the 32-KB cache block size for storage subsystems that require large data transfer, sequential, or high-bandwidth applications.

This parameter defines the supported cache block size for all of the logical drives in the storage subsystem. Not all controller types support all cache block sizes. For redundant configurations, this parameter includes all of the logical drives that are owned by both controllers within the storage subsystem.

Cache Flush Start and Cache Flush Stop

When you define values to start a cache flush, a value that is too low increases the chance that data needed for a host read is not in the cache. A low value also increases the number of disk drive writes that are necessary to maintain the cache level, which increases system overhead and decreases performance.

When setting storage subsystem cache settings, the value of the cacheFlushStart parameter must always be greater than or equal to the value of the cacheFlushStop parameter. For example, if the value of the cacheFlushStart parameter is set to 80, you may set the value of the cacheFlushStop parameter within the range of 0 to 80.

When you define values to stop a cache flush, the lower the value, the higher the chance that the data for a host read requires a disk drive read rather than reading from the cache.

Default Host Type

When you define host types, if Storage Partitioning is enabled, the default host type affects only those logical drives that are mapped in the default group. If Storage Partitioning is not enabled, all of the hosts that are attached to the storage subsystem must run the same operating system and be compatible with the default host type.

Media Scan Rate

Media scan runs on all of the logical drives in the storage subsystem that have Optimal status, do not have modification operations in progress, and have the mediaScanRate parameter enabled. Use the set logicalDrive command to enable or disable the mediaScanRate parameter.

Password

Passwords are stored on each storage subsystem. The password can be any combination of alphanumeric characters with a maximum of 30 characters.

Minimum Firmware Level

5.00 adds the defaultHostType parameter.

5.40 adds the failoverAlertDelay parameter.

6.14 adds the alarm parameter.

7.15 adds more cache block sizes.