CLI Guide

• 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 (offline). 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.
• If after 60 seconds from being quarantined the disk group is QTCR or QTDN, the disk group is
automatically dequarantined. The inaccessible disks are marked as failed and the disk group status
changes to CRIT (critical) or FTDN (fault tolerant with a down disk). If the inaccessible disks later come
online, they are marked as LEFTOVR (leftover).
• The dequarantine command is used to manually dequarantine the disk group. If the inaccessible disks
later come online, they are marked as LEFTOVR (leftover). If event 172 was logged, do not use the
dequarantine command. Instead follow the event’s recommended-action text. If event 485 was
logged, use the dequarantine command only as specified by the event’s recommended-action text to
avoid data corruption or loss.
When a disk group is dequarantined, event 173 is logged.
A quarantined disk group can be fully recovered if the inaccessible disks are restored. Make sure that all disks
are properly seated, that no disks have been inadvertently removed, and that no cables have been unplugged.
Sometimes not all disks in the disk group power up. Check that all enclosures have restarted after a power
failure. If these problems are found and then fixed, the disk group recovers and no data is lost.
If the inaccessible disks cannot be restored (for example, they failed), and the disk group’s status is FTDN or
CRIT, and compatible spares are available to replace the inaccessible disks, reconstruction will automatically
begin.
If a replacement disk (reconstruct target) is inaccessible at power up, the disk group becomes quarantined.
When the disk is found, the disk group is dequarantined and reconstruction starts. If reconstruction was in
process, it continues where it left off.
NOTE:
The only commands allowed for a quarantined disk group are dequarantine and delete
vdisks and remove disk-groups. If you delete a quarantined disk group and its inaccessible
disks later come online, the disk group will reappear as quarantined or offline and you must
delete it again (to clear those disks).
This command has a confirmation prompt in interactive console mode.
Minimum role
manage
Syntax
dequarantine
disk-group disk-group
76 Alphabetical list of commands