Raid5 w/ mdadm request for help.

chris lostpkts at gmail.com
Fri Sep 5 18:22:12 UTC 2008


On Fri, Sep 5, 2008 at 11:05 AM, Rashkae <ubuntu at tigershaunt.com> wrote:
>
> I sort of lost track of where things when horribly wrong and what you've
> done so far to fix.
>
> To clarify, if you remove the drives you've added, does the system
> recover md0 and work? or is your data housing array now hosed?
>


Ok... I did the following since the post.

mdadm --stop /dev/md1
mdadm --zero-superblock /dev/sd[ijklmnops]1

This wiped them off and I then recreated the array.

mdadm --create --verbose /dev/md1 --level=5 --raid-devices=8 /dev/sd[ijklmnop]1

while it was creating that I added /dev/sds1 into the mix as a spare.

mdadm --add /dev/md1 /dev/sds1

Things appear to be ok, but have 2 questions.

1/ when I do a   mdadm --examine --scan   *2* md0 show up.
2/ and md1 shows 2 spares but only has 1.

root at hoth:~# mdadm --examine --scan
ARRAY /dev/md0 level=raid5 num-devices=7
UUID=c08f16fe:f0fb7dec:44e33c5a:20ebc66f
   spares=1
ARRAY /dev/md0 level=raid5 num-devices=8
UUID=a3ea7714:de2bf962:98512988:9ff2ba5b
   spares=1
ARRAY /dev/md1 level=raid5 num-devices=8
UUID=e0fccd56:52b6dfc6:98512988:9ff2ba5b
   spares=2


root at hoth:~# cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
[raid4] [raid10]
md1 : active raid5 sds1[8](S) sdp1[9] sdo1[6] sdn1[5] sdm1[4] sdl1[3]
sdk1[2] sdj1[1] sdi1[0]
      2734961152 blocks level 5, 64k chunk, algorithm 2 [8/7] [UUUUUUU_]
      [====>................]  recovery = 21.3% (83379072/390708736)
finish=400.5min speed=12784K/sec

md0 : active raid5 sdb1[0] sdf1[8](S) sdh1[7] sdg1[6] sde1[5] sdr1[4]
sdc1[3] sdd1[2] sda1[1]
      3418687552 blocks level 5, 64k chunk, algorithm 2 [8/8] [UUUUUUUU]

unused devices: <none>



So I'm guessing teh 2 spares is b/c it is rebuilding and will change
to 1 when it's done.  But unsure.

My big worry is the 2 md0's.   I have
ARRAY /dev/md0 level=raid5 num-devices=8 spares=1
UUID=a3ea7714:de2bf962:98512988:9ff2ba5b

in my mdadm.conf file.  So it comes up correctly on reboot.

Is there a way of purging the old/bad md0 without borking the current md0?

Thanks
chris




More information about the ubuntu-users mailing list