Bug#382263: mdadm: /dev/md0 lost also

[Arthur Marsh]

Package: mdadm
Version: 2.5.2-10
Followup-For: Bug #382263


After rebooting following the last mdadm upgrade, dmesg reported:

md: md driver 0.90.3 MAX_MD_DEVS=256, MD_SB_DISKS=27
md: bitmap version 4.39
md: raid1 personality registered for level 1
md: md0 stopped.
md: bind<hdb3>
md: bind<hda3>
raid1: raid set md0 active with 2 out of 2 mirrors
Attempting manual resume

Then bootlog reported:

Thu Aug 10 02:21:36 2006: Assembling RAID array md0...done (already 
running).
Thu Aug 10 02:21:37 2006: Will now check all file systems.
Thu Aug 10 02:21:37 2006: fsck 1.39 (29-May-2006)
Thu Aug 10 02:21:37 2006: Checking all file systems.
Thu Aug 10 02:21:37 2006: [/sbin/fsck.ext3 (1) -- /mirror3] fsck.ext3 -a 
-C0 /de
v/md0
Thu Aug 10 02:21:37 2006: fsck.ext3: No such file or directory while 
trying to o
pen /dev/md0
Thu Aug 10 02:21:37 2006: /dev/md0:
Thu Aug 10 02:21:37 2006: The superblock could not be read or does not 
describe
a correct ext2
Thu Aug 10 02:21:37 2006: filesystem.  If the device is valid and it 
really cont
ains an ext2
Thu Aug 10 02:21:37 2006: filesystem (and not swap or ufs or something 
else), th
en the superblock
Thu Aug 10 02:21:37 2006: is corrupt, and you might try running e2fsck 
with an a
lternate superblock:
Thu Aug 10 02:21:37 2006:     e2fsck -b 8193 <device>
Thu Aug 10 02:21:37 2006:
Thu Aug 10 02:21:37 2006: fsck died with exit status 8

As a quick hack I was able to mount the mirrored /dev/hda3 /dev/hdb3 
using /dev/md/0 instead of the missing /dev/md0 as shown in the mount 
output below.



-- Package-specific info:
--- mount output
/dev/hda5 on / type ext3 (rw,errors=remount-ro)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
usbfs on /proc/bus/usb type usbfs (rw)
tmpfs on /dev/shm type tmpfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/hda7 on /symonec type vfat (rw,uid=65534,gid=65534,umask=000,iocharset=utf8)
/dev/hda1 on /victoriac type vfat (rw,uid=65534,gid=65534,umask=000)
/dev/hdb1 on /victoriad type vfat (rw,uid=65534,gid=65534,umask=000,iocharset=utf8)
tmpfs on /dev type tmpfs (rw,size=10M,mode=0755)
//10.0.0.2/chocolatec on /chocolatec type cifs (rw,mand)
//10.0.0.2/SharedDocs on /chocolateSharedDocs type cifs (rw,mand)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
/dev/md/0 on /mirror3 type ext3 (rw,errors=remount-ro)

--- mdadm.conf
DEVICE partitions
CREATE owner=root group=disk mode=0660 auto=yes metadata=1
ARRAY /dev/md/0 level=raid1 num-devices=2 UUID=050adb28:53f34c07:56f17a91:cbb41e2a
MAILADDR root

--- /proc/mdstat:
Personalities : [raid1] 
md0 : active raid1 hda3[0] hdb3[1]
      6048384 blocks [2/2] [UU]
      
unused devices: <none>

--- /proc/partitions:
major minor  #blocks  name

   3     0   39082680 hda
   3     1   14337981 hda1
   3     3    6052032 hda3
   3     5   10071936 hda5
   3     6     975712 hda6
   3     7    7636576 hda7
   3    64   39082680 hdb
   3    65   31249938 hdb1
   3    67    6048472 hdb3
   3    69     750030 hdb5
   9     0    6048384 md0

--- initrd.img-2.6.17:
20975 blocks
scripts/local-top/mdadm
sbin/mdadm
etc/udev/mdadm.rules
lib/modules/2.6.17/kernel/drivers/md/multipath.ko
lib/modules/2.6.17/kernel/drivers/md/raid5.ko
lib/modules/2.6.17/kernel/drivers/md/md-mod.ko
lib/modules/2.6.17/kernel/drivers/md/raid0.ko
lib/modules/2.6.17/kernel/drivers/md/raid10.ko
lib/modules/2.6.17/kernel/drivers/md/xor.ko
lib/modules/2.6.17/kernel/drivers/md/raid1.ko
lib/modules/2.6.17/kernel/drivers/md/linear.ko
lib/modules/2.6.17/kernel/drivers/md/raid6.ko

--- /proc/modules:
dm_mod 50712 0 - Live 0xc0bce000
raid1 21216 1 - Live 0xc0853000
md_mod 69748 2 raid1, Live 0xc08da000

--- volume detail:


-- System Information:
Debian Release: testing/unstable
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.17
Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8)

Versions of packages mdadm depends on:
ii  debconf [debconf-2.0]         1.5.3      Debian configuration management sy
ii  libc6                         2.3.6-18   GNU C Library: Shared libraries
ii  lsb-base                      3.1-12     Linux Standard Base 3.1 init scrip
ii  makedev                       2.3.1-82   creates device files in /dev

Versions of packages mdadm recommends:
ii  exim4-daemon-light [mail-tran 4.62-4     lightweight exim MTA (v4) daemon

-- debconf information:
* mdadm/autostart: true
  mdadm/initrdstart: all
* mdadm/warning:
* mdadm/start_daemon: true
* mdadm/mail_to: root
* mdadm/autocheck: true