On a debian system my home directory is on a raid1 md array. After creation it worked fine for some time, but once the second drive disappeared from the array.
# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sda3[1]
1843414335 blocks super 1.2 [2/1] [U_]
When I manually add the missing disk it is detected as spare and array is reconstructed. Until the next reboot...
I managed to fix it by recreating the array (with the same partitions). It lasts for several reboots and now again the same issue.
Both disks are new, SMART checks are ok.
I have checked dmesg
and here is the full "failing" sequence:
Good synced RAID :
Number Major Minor RaidDevice State
0 8 3 0 active sync /dev/sda3
1 8 19 1 active sync /dev/sdb3
On reboot (more dmesg
here: http://pastebin.com/q1Du95Tv ):
[ 8.175247] sda: sda1 sda2 sda3 sda4
...
[ 8.644777] md: md0 stopped.
[ 8.645248] md: bind<sda3>
[ 8.646198] md: raid1 personality registered for level 1
[ 8.646377] md/raid1:md0: active with 1 out of 2 mirrors
[ 8.646391] md0: detected capacity change from 0 to 42916118528
[ 8.646407] RAID1 conf printout:
[ 8.646409] --- wd:1 rd:2
[ 8.646411] disk 0, wo:0, o:1, dev:sda3
[ 8.648749] md0: unknown partition table
[ 8.753331] usb 4-3: new full-speed USB device number 7 using ohci-pci
[ 8.840857] sdb: sdb1 sdb2 sdb3 sdb4
[ 8.841175] sd 1:0:0:0: [sdb] Attached SCSI disk
After this:
Number Major Minor RaidDevice State
0 8 3 0 active sync /dev/sda3
2 0 0 2 removed
mdadm -E
result: http://pastebin.com/cp65mNQh