[CentOS] C7 and mdadm

Wed Jan 23 06:02:11 UTC 2019
Gordon Messmer <gordon.messmer at gmail.com>

On 1/22/19 2:26 PM, mark wrote:
> A user's system had a hard drive failure over the weekend. Linux RAID 6...
> But: it's now
> Personalities : [raid6] [raid5] [raid4]
> md0 : active (auto-read-only) raid5 sdg1[8](S) sdh1[7] sdf1[4] sde1[3]
> sdd1[2] sdc1[1]
>        23441313792 blocks super 1.2 level 5, 512k chunk, algorithm 2 [7/5]
> [_UUUU_U]

That doesn't look like RAID 6.  That looks like RAID 5 with a hot 
spare.  There appear to be two drives missing.  If you can locate one of 
those two drives and add it to the array, you should be able to start it 
and mount the filesystem.   Otherwise you'll have to restore backups.

The drive that failed this weekend may work well enough to add it to the 
array temporarily if you need to refresh your backups.