Bug#539959: mdadm: allow updating preferred minor of an active array

[Frédéric Brière]

Package: mdadm
Version: 3.0-2
Severity: wishlist

AFAIK, while it's possible to update the preferred minor of an array
when assembling it, it's not possible to do so for an array that's
already assembled and running.

A few months ago, I wanted to clean up my arrays (which had been
numbered haphazardly), but I obviously could not shut down the one
holding the root partition.  My naive attempt was to edit
/etc/mdadm/mdadm.conf, and hope that mdadm would nicely go along and
build them correctly on the next reboot.  That was far from successful,
and I had to resort to a rescue CD to get out of the mess I'd created.

It'd be nice to be able to update the preferred minor of such an array,
even if it only kicks in on the next reboot.


-- Package-specific info:

-- System Information:
Debian Release: squeeze/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: i386 (i686)

Kernel: Linux 2.6.26.8 (SMP w/1 CPU core)
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages mdadm depends on:
ii  debconf                       1.5.27     Debian configuration management sy
ii  libc6                         2.9-23     GNU C Library: Shared libraries
ii  lsb-base                      3.2-23     Linux Standard Base 3.2 init scrip
ii  makedev                       2.3.1-89   creates device files in /dev
ii  udev                          0.141-1    /dev/ and hotplug management daemo

Versions of packages mdadm recommends:
ii  module-init-tools            3.9-2       tools for managing Linux kernel mo
ii  postfix [mail-transport-agen 2.6.2~rc1-1 High-performance mail transport ag

mdadm suggests no packages.

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