Difference between revisions of "Mdadm"
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(Created page with "== Remove a drive from an active array == <pre> mdadm --manage /dev/md0 --fail /dev/sdX # set the drive as failed mdadm --manage /dev/md0 --remove /dev/sdX # remove the drive...") |
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== Check array status == | == Check array status == | ||
Both <code>cat /proc/mdstat</code> and <code>mdadm --detail /dev/md0</code> have detailed output about configured arrays. | Both <code>cat /proc/mdstat</code> and <code>mdadm --detail /dev/md0</code> have detailed output about configured arrays. | ||
| + | |||
| + | == Possible issues == | ||
| + | === Array refuses to rebuild when in a degraded state and a new drive is added === | ||
| + | The array might be frozen: | ||
| + | <pre> | ||
| + | root@galaxy:~# cat /sys/block/md0/md/sync_action | ||
| + | frozen | ||
| + | </pre> | ||
| + | So give it a nudge: | ||
| + | <pre> | ||
| + | root@galaxy:~# echo idle > /sys/block/md0/md/sync_action | ||
| + | root@galaxy:~# cat /sys/block/md0/md/sync_action | ||
| + | recover | ||
| + | </pre> | ||
Latest revision as of 12:47, 22 March 2015
Contents
Remove a drive from an active array
mdadm --manage /dev/md0 --fail /dev/sdX # set the drive as failed mdadm --manage /dev/md0 --remove /dev/sdX # remove the drive from the array
Add a drive to an active and degraded array
mdadm --manage /dev/md0 --add /dev/sdX # add the drive
Check array status
Both cat /proc/mdstat and mdadm --detail /dev/md0 have detailed output about configured arrays.
Possible issues
Array refuses to rebuild when in a degraded state and a new drive is added
The array might be frozen:
root@galaxy:~# cat /sys/block/md0/md/sync_action frozen
So give it a nudge:
root@galaxy:~# echo idle > /sys/block/md0/md/sync_action root@galaxy:~# cat /sys/block/md0/md/sync_action recover
