Comment 19 for bug 75681

Revision history for this message
Ian Jackson (ijackson) wrote : Re: [Bug 75681] Re: initramfs script: race condition between sata and md

Reinhard Tartler writes ("Re: [Bug 75681] Re: initramfs script: race condition between sata and md"):
> Ian Jackson <email address hidden> writes:
> > 2. Run
> > /scripts/local-top/mdadm from-udev
> > (NB `from-udev' is an argument you must pass to the script)
> > and see if it fixes it. (If so it will show up in /proc/partitions
> > and be mountable.)
>
> Running that script makes /dev/md[1..3] come up in non-degraded mode,
> md0 stays in degraded mode. LVM is not started automatically. After
> typing 'lvm vgscan ; lvm vgchange -ay', my LVMs come up and I can
> continue booting with CTRL-D.

udev is supposed to do all of these things. It's supposed to
automatically activate the LVM when the md devices appear, too. I
don't know why it isn't, yet.

Could you please boot with break=premount, and do this:
 udevd --verbose >/tmp/udev-output 2>&1 &
 udevtrigger
At this point I think you will find that your mds and lvms
are not activated properly; check with
 cat /proc/partitions

If as I assume they aren't:
 pkill udevd
 udevd --verbose >/tmp/udev-output2 2>&1 &
        /scripts/local-top/mdadm from-udev

And now your mds should all be activated but hopefully the LVM bug
will recur. So:
 pkill udevd
 lvm vgscan
 lvm vgchange -a y
 mount /dev/my-volume-group/my-volume-name /root
        cp /tmp/udev-output* /root/root/.
        exit

And then when the system boots attach /root/udev-output* and your
initramfs to this bug report.

mdadm_2.5.6-7ubuntu4 ought to fix the fact that md0 comes up in
degraded mode but please don't upgrade to it yet as it may perturb the
other symptoms out of existence.

Thanks,
Ian.