Bug#552130: mdadm: possibly a byte order problem?

[Bjørn Mork]

Package: mdadm
Version: 2.6.7.2-3
Followup-For: Bug #552130

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I just noticed something that might explain this bug (unless it's
just a display problem).  Note the differences between the UUIDs
for the array and the corresponding bitmap file.  Looks like the
byte order is reversed in the bitmap:

canardo:/etc# mdadm --verbose --detail /dev/md2
/dev/md2:
        Version : 00.90
  Creation Time : Tue Oct 13 18:58:33 2009
     Raid Level : raid5
     Array Size : 3907028992 (3726.03 GiB 4000.80 GB)
  Used Dev Size : 1953514496 (1863.02 GiB 2000.40 GB)
   Raid Devices : 3
  Total Devices : 3
Preferred Minor : 2
    Persistence : Superblock is persistent

    Update Time : Sat Jan 16 12:03:32 2010
          State : active, resyncing
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

 Rebuild Status : 16% complete

           UUID : 6c4c0385:4f0b4770:7067137c:e3b1885e (local to host canardo)
         Events : 0.43

    Number   Major   Minor   RaidDevice State
       0       8       64        0      active sync   /dev/sde
       1       8       80        1      active sync   /dev/sdf
       2       8       96        2      active sync   /dev/sdg
canardo:/etc# mdadm --examine-bitmap /boot/md2-raid5-bitmap
        Filename : /boot/md2-raid5-bitmap
           Magic : 6d746962
         Version : 4
            UUID : 85034c6c:70470b4f:7c136770:5e88b1e3
          Events : 32
  Events Cleared : 32
           State : OK
       Chunksize : 2 MB
          Daemon : 5s flush period
      Write Mode : Normal
       Sync Size : 1953514496 (1863.02 GiB 2000.40 GB)
          Bitmap : 953865 bits (chunks), 0 dirty (0.0%)


Is this the reason why the bitmap always is ignored on reassembly?

My /etc/mdadm/mdadm.conf contains
ARRAY /dev/md2 level=raid5 num-devices=3 bitmap=/boot/md2-raid5-bitmap UUID=6c4c0385:4f0b4770:7067137c:e3b1885e



Bjørn


- -- System Information:
Debian Release: 5.0.3
  APT prefers stable
  APT policy: (700, 'stable'), (650, 'testing'), (600, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.26-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages mdadm depends on:
ii  debconf                   1.5.24         Debian configuration management sy
ii  libc6                     2.7-18         GNU C Library: Shared libraries
ii  lsb-base                  3.2-20         Linux Standard Base 3.2 init scrip
ii  makedev                   2.3.1-88       creates device files in /dev
ii  udev                      0.125-7+lenny3 /dev/ and hotplug management daemo

Versions of packages mdadm recommends:
ii  module-init-tools             3.4-1      tools for managing Linux kernel mo
ii  sendmail-bin [mail-transport- 8.14.3-5   powerful, efficient, and scalable 

mdadm suggests no packages.

- -- debconf information:
* mdadm/autostart: true
* mdadm/initrdstart: /dev/md0 /dev/md1
  mdadm/initrdstart_notinconf: false
  mdadm/initrdstart_msg_errexist:
  mdadm/initrdstart_msg_intro:
  mdadm/initrdstart_msg_errblock:
* mdadm/start_daemon: true
* mdadm/mail_to: root
  mdadm/initrdstart_msg_errmd:
  mdadm/initrdstart_msg_errconf:
* mdadm/autocheck: true

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