Support mdadm metadata version 0.91 (used during reshape)

[Roderik van der Veer]

Binary package hint: grub2

I've got a following setup

Quad code intel
8gb memory
6 x 1TB sata disk, in a raid5 array

I've installed maveric i386 on a 4x 1TB array. It boots just fine.
I've added the two other disks, and i'm currently reshaping the array to include the two extra disks. (i mention this because maybe it's relevant, some locking that prevents update-grub from accessing the disks?)

I've run dist upgrade this morning, no problems, but i noticed just now that only 3GB memory was available. So i installed the pae kernel to fix this. Also tried to install the server kernel

Suddenly, i get a lot of errors from grub-update. During apt-get and by hand.

root@tenedos:~# update-grub
Generating grub.cfg ...
error: unsupported RAID version: 0.91.
error: unsupported RAID version: 0.91.
error: unsupported RAID version: 0.91.
error: unsupported RAID version: 0.91.
error: unsupported RAID version: 0.91.
error: unsupported RAID version: 0.91.
/usr/sbin/grub-probe: error: no such disk.

An update was available for grub-pc so i installed that one as well, no improvement.
No real info to be found on google.

I'm afraid to reboot, since i don't think it will boot anymore.

[Roderik van der Veer (roderik)]

Reinstalling grub got this fixed: http://ubuntuforums.org/showthread.php?p=9878825

[Colin Watson (cjwatson)]

Here's what the mdadm documentation says:

  When a version 0.90 array is being reshaped (e.g. adding extra devices to a RAID5), the version number is temporarily set to 0.91. This ensures that if the reshape process is stopped in the middle (e.g. by a system crash) and the machine boots into an older kernel that does not support reshaping, then the array will not be assembled (which would cause data corruption) but will be left untouched until a kernel that can complete the reshape processes is used.

So simply waiting would have been enough to work around this, but GRUB ought to recognise this format anyway since I *believe* it's equivalent to 0.90 for the purposes of reading.

[Ikus-Soft (ikus-soft)]

I still have this bug in Ubuntu hardy 10.04.2 LTS (server or desktop).

It would be nice just to change the error message to be more specific about the problem being mdadm reshaping the RAID.

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for grub2 (Ubuntu) because there has been no activity for 60 days.]