The storage cluster is designed to automatically adapt when a volume (hard drive) or node fails for any reason. Swarm checks every storage cluster volume during the node startup procedure, and it tracks any gaps in service that would trigger a status change:
- If a
A volume is
disconnected from the cluster for more than 2 weeks, it isconsidered "stale" and its contents cannot be used unless an administrator specifically overrides this process
.If a node is shut downif disconnected from the cluster for more than 2 weeks
,.
A node and all of its volumes are considered stale and cannot be used if it is shut down for more than 2 weeks.
The "stale" status is triggered by a service gap of 2 weeks, which is the default value for the disk.obsoleteTimeout setting.
You can force Force a volume remount by modifying the disk.volumes setting and adding the :k (keep) policy option. You can also return Return them to service dynamically (either remounting or reformatting) using SNMP. (v9.3)
...
Reformatting the volume allows it to be filled by the health processor (HP) in an orderly fashion. Doing so prevents creating excessive work for the health processor and prevents generating trapped space that will need needed to be reclaimed.
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snmpset -v2c -c ourpwdofchoicehere -m ./CARINGO-MIB.txt:./CARINGO-CASTOR-MIB.txt 192.168.99.100 castorFormatStaleVolumeAction s "/dev/sda" |
| Info |
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ImportantThe volume's encryption status is always retained on return to service; physical removal from Swarm is required to change it. |
Remounting volumes
It is rarely desirable to remount a volume that has stale content. The volume's missing content will have been is recovered by this time and so the cluster will have has its full complement of replicas of the cluster's content. Adding extra replicas will create creates work for the health processor to sift through the replicas, cleaning up redundant and obsolete copies. This cleanup will create creates trapped space in the cluster that will take several HP cycles to reclaim.
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| title | NoteWhen you force a stale volume back into service, be aware that you could inadvertently resurrectBe aware content that was explicitly deleted by clients can be inadvertently resurrected when forcing a stale volume back in to service. This is not a problem for content automatically deleted by lifepoint policies because the obsolete content will beis discovered and deleted by the Swarm health processor. |
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snmpset -v2c -c ourpwdofchoicehere -m ./CARINGO-MIB.txt:./CARINGO-CASTOR-MIB.txt 192.168.99.100 castorRemountStaleVolumeAction s "/dev/sda" |