[->UUIDudev] new array not assembled correctly after reboot

[dogandp]

Binary package hint: mdadm

I'm not sure of what actually caused this bug, so I'll give some background:

I have a lot of raid arrays, run off of various partitions on several disks. Everything was working fine - when I would create a new array, upon reboot it would automatically be detected correctly. For safety, I would habitually cat /proc/mdstat > logfile to make sure if there WERE any problems I could manually reassemble it.

At some point I upgrades to 9.04, but I THINK it was before any problems started.

The trigger in my mind was trying to create md66. It created fine, but now upon reboot, a single drive from that array gets assigned to an inactive array, md_d6. In order to get md66 back (which I actually reassembled now as md6), I need to send a bunch of --stop's to md_d6 - it seems, one for each drive in md66, and then I can do an assemble and it works fine.

This problem persists every reboot.

Since then, I have created md7, and the problem also affects THAT array - and also, md10. All of the arrays need to be assembled manually upon reboot.

Is this related to having tried to create md66? or is this a coincendence masking something else? I couldn't find much info here on any of this - nor on the meaning of md_d vs md ...

:~# lsb_release -rd
Description: Ubuntu 9.04
Release: 9.04
:~# apt-cache policy mdadm
mdadm:
  Installed: 2.6.7.1-1ubuntu8
  Candidate: 2.6.7.1-1ubuntu8
  Version table:
 *** 2.6.7.1-1ubuntu8 0
        500 http://us.archive.ubuntu.com jaunty/main Packages
        100 /var/lib/dpkg/status

[dogandp (ubuntu-dogandpanda)]

I should elaborate - all arrays created BEFORE md66 still autoassemble perfectly.

[ceg (ceg)]

I think it was in 9.04 when udev switched to use mdadm --incremental.

So you reported what's discussed at http://ubuntuforums.org/showthread.php?p=8407182, and experience those
Bug #550131 initramfs missing /var/run/mdadm dir (loosing state)
Bug #136252 [->UUIDudev] mdadm.conf w/o ARRAY lines but udev/mdadm not assembling arrays. (boot fails)

[ceg (ceg)]

Your old arrays probably work because they got written to mdadm.conf during the update.

[ceg (ceg)]

workaround:

# start your arrays manualy
# /usr/share/mdadm/mkconf force-generate /etc/mdadm/mdadm.conf
# update-initramfs -k all -u

[ceg (ceg)]

The workaround generates a mdadm.conf describing active arrays and updates the initramfs for all kernels, so they will contain the new file.

[Surbhi Palande (csurbhi)]

@dogandp, do you still see the bug?
The workaround that ceg has suggested, seems to be a standard method, when you create a MD array after installation. This is because, by default md does not update initramfs. So you need to do this manually.

A safer way is to first check the contents of /etc/mdadm/mdadm.conf and the output of /usr/share/mdadm/mkconf. mkconf only shows the output of *existing active* arrays. If you already have definitions of array which are not active right now, but you may like to see them active later, then these definitions will be overwritten by mkfconf force-generate.

Marking the bug as Invalid right now as this updating initramfs is expected in such cases. Please do reopen the bug, if you still see it inspite of updating initramfs.