Trust - HP P2000 G3 Cli Reference Manual

trust

Description Enables an offline vdisk to be brought online for emergency data recovery. This command must be
enabled before each use. If used improperly this command can cause unstable operation and data
loss; before use, carefully read the cautions and procedures below. The trust command output is
shown in console mode but not in XML API mode.
The trust command provides an opportunity to recover data from a vdisk that has gone offline due
to disk failure. The command forces a resynchronization of the metadata (as well as time and date
stamps) that unifies members of a vdisk, and essentially puts the vdisk back into an accessible state.
As long as the failed disks are operable, data can be read from the disks and restored to another
location.
From examining the state of the disks, if the command determines that the trust operation is
unsafe–that it may result in an unstable vdisk with data corruption–the command will fail. You may
then seek assistance from technical support or run the command with a special parameter to
acknowledge the risk of proceeding. Otherwise, if the command determines the operation to be
safe, the command will proceed.
When the "trusted" vdisk is back online, back up its data and audit the data to make sure that it is
intact. Then delete that vdisk, create a new vdisk, and restore data from the backup to the new vdisk.
Using a trusted vdisk is only a disaster-recovery measure; the vdisk has no tolerance for any
additional failures.
The following procedure outlines the general steps for performing a trust operation. Before starting
this procedure, consult the online troubleshooting guide at
https://www.hp.com/go/p2000/troubleshooting
to your situation and for guidance to perform it.
CAUTION:
1. Do not use the trust command when the storage system is unstable; for example, if there are
many power or topology-change events.
2. The trust command cannot be run on a quarantined vdisk. In many cases the vdisk will be
automatically dequarantined. If you cannot resolve the issue that caused the disk to become
quarantined such that it is automatically dequarantined, and if the trust operation is applicable to
your situation, dequarantine the vdisk, confirm it is in offline state by using the show vdisks
command, and then proceed to trust.
3. Never update controller-module, expansion-module, or disk firmware when the vdisk is offline.
4. Never clear unwritten data cache when a vdisk is offline.
5. Do not use the trust command on a vdisk that went offline during vdisk expansion.
6. Do not use the trust command on a vdisk with status CRIT. Instead, add spares and let the
system reconstruct the vdisk.
Steps for running the trust command
1. Disable background scrub of disks and vdisks to avoid running scrubs automatically.
2. Identify the cause for the vdisk going offline.
3. If an external issue (power, cabling, and so forth) caused the vdisk to go offline, fix the external
issue before continuing to the next step.
4. Disable host access to the offline vdisk. In a single-controller configuration, disconnect the
host-port cables. In a dual-controller configuration:
a. Determine the owning controller of the offline vdisk.
b. As a precautionary measure, remove the host-port cables of the owning controller of the
offline vdisk.
5. Unseat the spare disks associated with the vdisk to prevent reconstruction.
332 Alphabetical list of commands
to determine if the trust operation is applicable