dequarantine
55
dequarantine
Description
Removes a disk group from quarantine.
CAUTION:
Carefully read this topic to determine whether to use the
dequarantine
command to
manually remove a disk group from quarantine. The
dequarantine
command should only be used
as part of the emergency procedure to attempt to recover data and is normally followed by use of the
CLI
command. If a disk group is manually dequarantined and does not have enough disks to
continue operation, its status will change to
OFFL
and its data may or may not be recoverable
through use of the
command. It is recommended that you contact technical support for
assistance in determining if the recovery procedure that makes use of the
dequarantine
and
commands is applicable to your situation and for assistance in performing it. Also, see the help for
the
command.
To continue operation and 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, and a
RAID-10 or RAID-50 disk group can have only one inaccessible disk per subgroup. 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 (“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. For recommended actions for
these events, see the Event Descriptions Reference Guide.
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
(fault tolerant and online), 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
(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.
Summary of Contents for AssuredSAN 6004
Page 11: ...Document conventions and symbols 11 TIP Provides helpful hints and shortcuts...
Page 114: ...114 Alphabetical list of commands See also set cli parameters show protocols...
Page 139: ...show controller statistics 139 See also reset all statistics reset controller statistics...
Page 162: ...162 Alphabetical list of commands See also show power supplies...
