HP MSA 2040 CLI Reference Guide

36 Alphabetical list of commands

clear cache

Description Clears unwritable cache data from both controllers. This data cannot be written to disk because it is

associated with a volume that no longer exists or whose disks are not online. If the data is needed,

the volume's disks must be brought online. If the data is not needed it can be cleared, in which case

it will be lost and data will differ between the host and disk. Unwritable cache is also called orphan

data.

NOTE: Only use this command when all vdisks are online. Improper use of this command may

result in data loss.

You can clear unwritable cache data for a specified volume or for all volumes.

If unwritable data exists for more than one volume and you specify the volume parameter, the

command will clear unwritable data for that volume only.

If unwritable data exists for more than one volume and you omit the volume parameter, the

command will clear unwritable data for the first volume only and you must re-run the command for

each remaining volume.

Use the following process to ensure all cache data has been cleared.

1. Run the show unwritable-cache command to view the percent of unwritable cache in each

controller.

2. Run the clear cache command.

3. Run the show unwritable-cache command to view the percent of unwritable cache in each

controller. If the value is not 0, repeat steps 1–3 until the value is 0.

Syntax

clear cache

[volume

volume

]

Parameters volume

volume

Optional. The name or serial number of a specific volume for which to clear unwritable cache data.

For volume syntax, see "Command syntax" (page 20).

Example Clear unwritable cache data for volume V1 from both controllers:

# clear cache volume v1

Success: Command completed successfully - If unwritable cache data existed, it

has been cleared. (2012-01-18 14:21:11)