Bug#789152: boot fails using root=UUID= for root-device on software, raid /dev/md*

[Chris Vogel]

Hi Michael,

thanks for the prompt answer!

On 18.06.2015 13:31, Michael Biebl wrote:
> But mdadm (in jessie) ships it's own initramfs-tools hook
> /usr/share/initramfs-tools/hooks/mdadm which is supposed to copy that
> rules file into the initramfs.

Thanks for this information I missed. I looked at the file and found 
that the udev rule will only be copied to initramfs under two 
conditions: 1) There are md devices configured in /etc/mdadm/mdadm.conf 
and 2) INITRDSTART in /etc/default/mdadm contains a list of arrays to 
start or 'all'.

This behavior is different from Wheezy in which the udev rule was always 
copied (probably by the udev hook from the udev packet).

This change is the reason why my Jessie systems copied from a non 
software raid server on a new filesystem on a software raid device does 
not work any longer.

> In any case, this looks like something which should be handled in the
> mdadm package and I'm inclined to re-assign this bug, unless the mdadm
> maintainers disagree (CCed).

I totally agree after looking at the hook which comes with mdadm.

> As for /usr/share/initramfs-tools/hooks/udev, I guess we should drop the
> copy rules for the following files
>
> - 64-md-raid.rules (mdadm, replaced by 63-md-raid-arrays.rules,
> 64-md-raid-assembly.rules)

Having the copy rules in two places is at least misleading while 
debugging problems...


Thanks again for the prompt answer!

Chris.