Ubuntu
mdadm package

  1. Bug #1171945
  2. Comment #21

Comment 21 for bug 1171945

Revision history for this message
tarantoga (tarantoga-2) wrote :

I am also affected by this regression.
It looks like Wheezy disables udev for md and uses an rc-script for assembling at boot; therefore it will not automatically assemble arrays after boot.
Trusty assembles real devices during and after boot, but seems to ignore virtual devices like /dev/md0.

So I added a new rule for virtual devices to the existing udev rules in Trusty. I created /etc/udev/rules.d/85-mdadm.rules with this single line rule:

SUBSYSTEM=="block", ACTION=="add|change", ENV{ID_FS_TYPE}=="linux_raid_member", DEVPATH=="*/virtual/*", RUN+="/sbin/mdadm --incremental $tempnode"

This rule (plus the existing ones) assemble my nested raid during boot or any time later, but might not work for the root filesystem unless a initramfs-tools/hooks script is created (not tested).