Administrator Guide

NOTE: If the disk group is being scrubbed, but the Abort Scrub button is unavailable, a background scrub is in progress.
To stop the background scrub, disable the Disk Group Scrub option as described in Configuring system utilities on page
72.
4. Click Abort Scrub.
A message confirms that scrub has been aborted.
5. Click OK.
Removing a disk group from quarantine
Contact technical support for assistance in determining if the recovery procedure that makes use of the Dequarantine Disk
Group panel and the trust command is applicable to your situation and for assistance in performing it.
CAUTION: Carefully read this topic to determine whether to use the Dequarantine Disk Group panel to manually
remove a disk group from quarantine.
NOTE: For status descriptions, see Related Disk Groups table.
● The Dequarantine Disk Group panel should only be used as part of the emergency procedure to attempt to recover data and
is normally followed by use of the CLI trust command. If a disk group is manually dequarantined and does not have enough
disks to continue operation, its status will change to offline (OFFL) and its data may or may not be recoverable through use
of the trust command.
● See the help for the trust command.
● To continue operation—that is, not go to quarantined status—a RAID-3 or RAID-5 disk group can have only one inaccessible
disk; a RAID-6 disk group can have only one or two inaccessible disks; a RAID-10 or RAID-50 disk group can have only
one inaccessible disk per sub-disk group. For example, a 16-disk RAID-10 disk group can remain online (critical) with 8
inaccessible disks if one disk per mirror is inaccessible.
● The system will automatically quarantine a disk group having a fault-tolerant RAID level if one or more of its disks becomes
inaccessible, or to prevent invalid, or stale data that may exist in the controller from being written to the disk group.
Quarantine will not occur if a known-failed disk becomes inaccessible or if a disk becomes inaccessible after failover or
recovery. The system will automatically quarantine an NRAID or RAID-0 disk group to prevent invalid data from being written
to the disk group. If quarantine occurs because of an inaccessible disk, event 172 is logged. If quarantine occurs to prevent
writing invalid data, event 485 is logged.
Examples of when quarantine can occur are:
● At system power-up, a disk group has fewer disks online than at the previous power-up. This may happen because a disk
is slow to spin up or because an enclosure is not powered up. The disk group will be automatically dequarantined if the
inaccessible disks come online and the disk group status becomes FTOL, or if after 60 seconds the disk group status is
QTCR or QTDN.
● During system operation, a disk group loses redundancy plus one more disk. For example, three disks are inaccessible in a
RAID-6 disk group or two disks are inaccessible for other fault-tolerant RAID levels. The disk group will be automatically
dequarantined if after 60 seconds the disk group status is FTOL, FTDN, or CRIT.
Quarantine isolates the disk group from host access and prevents the system from changing the disk group status to OFFL. The
number of inaccessible disks determines the quarantine status, from least to most severe:
● QTDN (quarantined with a down disk): The RAID-6 disk group has one inaccessible disk. The disk group is fault tolerant but
degraded. If the inaccessible disks come online or if after 60 seconds from being quarantined the disk group is QTCR or
QTDN, the disk group is automatically dequarantined.
● QTCR (quarantined critical): The disk group is critical with at least one inaccessible disk. For example, two disks are
inaccessible in a RAID-6 disk group or one disk is inaccessible for other fault-tolerant RAID levels. If the inaccessible disks
come online or if after 60 seconds from being quarantined the disk group is QTCR or QTDN, the disk group is automatically
dequarantined.
● QTOF (quarantined offline): The disk group is offline with multiple inaccessible disks causing user data to be incomplete, or is
an NRAID or RAID-0 disk group.
When a disk group is quarantined, its disks become write-locked, its volumes become inaccessible, and it is not available to
hosts until it is dequarantined. If there are interdependencies between the quarantined disk group's volumes and volumes in
other disk groups, quarantine may temporarily impact operation of those other volumes. Depending on the operation, the length
of the outage, and the settings associated with the operation, the operation may automatically resume when the disk group is
dequarantined or may require manual intervention. A disk group can remain quarantined indefinitely without risk of data loss.
A disk group is dequarantined when it is brought back online, which can occur in three ways:
● If the inaccessible disks come online, making the disk group FTOL, the disk group is automatically dequarantined.
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Working in the Pools topic