I recently inquired about adding a spare-disk to an operating RAID-5 array,
and was given the advice to use raidhotadd. I've tried this and want to make
sure that the result is the one I should expect. I thought that spare disks
would show up as an "unused device" in /proc/mdstat, but that may not be the
case???
This is my mdstat:
Personalities : [linear] [raid0] [raid1] [raid5]
read_ahead 1024 sectors
md0 : active raid5 hda2[3] sdc2[2] sdb2[1] sda2[0] 8305408 blocks level 5,
32k chunk, algorithm 2 [3/3] [UUU]
unused devices: <none>
The spare disk in this case is hda2[3], defined as a spare in /etc/raidtab.
Is this the way it should look? Can I be confident that hda2 will kick in if
one of the sd* fails? hda2 is of course formated exactly like the other
partitions.
Grateful for your advice!
Best regards,
Johan Ekenberg
