After booting, my RAID1 device (
/dev/md_d0 *) sometimes goes in some funny state and I cannot mount it.
* Originally I created
/dev/md0 but it has somehow changed itself into
# mount /opt mount: wrong fs type, bad option, bad superblock on /dev/md_d0, missing codepage or helper program, or other error (could this be the IDE device where you in fact use ide-scsi so that sr0 or sda or so is needed?) In some cases useful info is found in syslog - try dmesg | tail or so
The RAID device appears to be inactive somehow:
# cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md_d0 : inactive sda4(S) 241095104 blocks # mdadm --detail /dev/md_d0 mdadm: md device /dev/md_d0 does not appear to be active.
Question is, how to make the device active again (using
mdmadm, I presume)?
(Other times it's alright (active) after boot, and I can mount it manually without problems. But it still won't mount automatically even though I have it in
/dev/md_d0 /opt ext4 defaults 0 0
So a bonus question: what should I do to make the RAID device automatically mount at
/opt at boot time?)
This is an Ubuntu 9.10 workstation. Background info about my RAID setup in this question.
/etc/mdadm/mdadm.conf looks like this. I've never touched this file, at least by hand.
# by default, scan all partitions (/proc/partitions) for MD superblocks. # alternatively, specify devices to scan, using wildcards if desired. DEVICE partitions # auto-create devices with Debian standard permissions CREATE owner=root group=disk mode=0660 auto=yes # automatically tag new arrays as belonging to the local system HOMEHOST <system> # instruct the monitoring daemon where to send mail alerts MAILADDR <my mail address> # definitions of existing MD arrays # This file was auto-generated on Wed, 27 Jan 2010 17:14:36 +0200
/proc/partitions the last entry is
md_d0 at least now, after reboot, when the device happens to be active again. (I'm not sure if it would be the same when it's inactive.)
Resolution: as Jimmy Hedman suggested, I took the output of
mdadm --examine --scan:
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=de8fbd92[...]
and added it in
/etc/mdadm/mdadm.conf, which seems to have fixed the main problem. After changing
/etc/fstab to use
/dev/md0 again (instead of
/dev/md_d0), the RAID device also gets automatically mounted!