Bug#361408: mdadm: I have the same problem and some ideas

[Shawn Willden]

Package: mdadm
Version: 1.12.0-1
Followup-For: Bug #361408


I have the same problem, although I'm upgrading from 2.6.8 to 2.6.15.

What seems to happen is that during boot the md devices are being
detected and set up early and without regard to the minor numbers
that are specified in the superblocks.  The arrays are assembled
correctly, but they can end up assigned to any minor number.  In one 
case on my system, my root partition (which is normally md0) ended
up as md2.  Since the array that ended up as md0 didn't have a proper
filesystem on it (it's combined with other arrays in an LVM group),
the root filesystem could not be mounted.

I'm thinking that perhaps this problem is related to bugs 354705 and
354144.  According to 354705, mdrun doesn't honor the minor numbers 
in the md superblocks, which is what seems to be happening, and 
according to 354144, it is mdrun, not mdadm, that is used by the
initramfs to start the md arrays.

That doesn't really explain why it doesn't also happen with 2.6.8 and
2.6.11, though.  Perhaps a difference in the initramfs stuff (which
I don't understand at all, BTW).

-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.8-2-k7
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

Versions of packages mdadm depends on:
ii  debconf [debconf-2.0]         1.5.0      Debian configuration management sy
ii  libc6                         2.3.6-7    GNU C Library: Shared libraries
ii  makedev                       2.3.1-81   creates device files in /dev

mdadm recommends no packages.

-- debconf information:
* mdadm/autostart: true
* mdadm/warning:
* mdadm/start_daemon: true
* mdadm/mail_to: shawn at willden.org