On 14/12/2019 01:32, Angus Montgomery wrote:
Hi RAIDers I did a silly thing and now I'm stuck. I rebooted with an unstarted/in-progress raid5 reshape from 3 disks to 4 (reshape position is 0). The backup file is gone.
This looks very promising. The fact it's stuck at zero means that it hasn't started, so if we can force the revert, everything will be fine. Plus it's actually a well-known problem - I'm sure if you search the list archives you'll find plenty of examples of it. I'm sorry, though, I can't give you the fix off the top of my head.
One important detail you appear to have missed, though, that would be good is what version of linux / mdadm you're running. Can you give us the output of "uname -a" and "mdadm --version"?
I can't say for certain that it will work, but I strongly suspect if you get an up-to-date rescue CD with the latest mdadm, it'll sort out your revert, and then fix your reshape.
Note that you shouldn't need a backup file, and you're much better without one unless mdadm insists.
Cheers, Wol
