I've just done an upgrade on a system with a degraded mdadm array. It's been degraded for ages (yes, I'm very naughty) and it occasionally makes a big fuss about it but booting hasn't been a problem... Until now.

I now can't get past a beautiful error that outputs, waits 10 seconds and then repeats. It completely locks up the boot process and there are no live TTYs.

[ .... ] mdadm: sending ioctl 1261 to a partition!
[ .... ] mdadm: sending ioctl 1261 to a partition!
[ .... ] mdadm: sending ioctl 1261 to a partition!
[ .... ] mdadm: sending ioctl 1261 to a partition! 
** WARNING: There appears to be one or more degraded RAID devices **

The system may have suffered a hardware fault such as a disk drive
failure.  The root device may depend on the RAID devices being online. One
or moreof the following RAID devices are degraded:
Personalities: ...
md1 : active raid1 sda1[0]
      146...... blocks [2/1] [U_]

md0 : active raid5 .....
      .... (this is fine) .... [UUUU]

unused devices: <none>
Attempting to start the RAID in degraded mode...
mdadm: CREATE group disk not found
Started the RAID in degraded mode.

That just repeats over and over again.

I'm really suspicious of the mdadm: CREATE group disk not found message but haven't been able to find anything useful about it.

My aim here is to boot. If that means removing md1, I can live with that but I need help doing this from a live environment. However, I can't get rid of mdadm entirely because my accounts (and a lot of data) live on the okay array (md0).

More information available on request.

link|improve this question

67% accept rate
Ouch. I had to do some mdadm and lvm stuff from rescue mode once. It was not fun, but I can't remember for the life of me exactly what I did. – aking1012 Feb 13 at 18:21
Boot from the livecd, install mdadm, and inspect the disk(s) with mdadm -E. The results of that may be revealing. You also might check /proc/mdstat to see if the disk has been automatically connected to an array, and if not, try activating it with mdadm --assemble --run /dev/sdXX – psusi Feb 13 at 19:21
feedback

Know someone who can answer? Share a link to this question via email, Google+, Twitter, or Facebook.

Your Answer

 
or
required, but never shown

Browse other questions tagged or ask your own question.