[Bug 990913] Re: RAID goes into degrade mode on every boot 12.04 LTS server

[krutemp]

I all, I have the same problem with a fresh installation of Ubuntu
12.04.3 server, but I found a workaround that seems to work, without
reinstallation.

Problem:
I firstly installed the os on 2 hd configured as raid1 with swap (md0) and / (md1) partitions.
Secondly I added 2 more disks and via webmin I created a new raid1 with a single ext4 partition (md2) and have it mounted it at boot under /mnt/raid (again, via webmin).
It worked for a week, both md1 and md2, and very likely I updated the kernel image via aptitude (now I have 3.8.0-30-generic ) but I haven't rebooted it after. Today I needed to reboot it and it didn't. It didn't even show the boot messages.
At boot time, changing the boot options and removing the line gfx_mode $linux_gfx_mode, made it output the boot status messages, showing it was eventually ending to a initramfs console.
It did boot when choosing to use an older linux version from the boot menu (like 3.8.0-29-generic), even if during the boot process it asked if i wanted to skip the raid setup for md2. With the previous image it showed the boot output.
However, it was not able to mount md2 and showed a new raid md127.

Solution:
So after reading this report and other pages, here is the workaround I used:
1. booted with a previous version and logged in
2. changed /etc/mdadm/mdadm.cnf
From:
# definitions of existing MD arrays
ARRAY /dev/md/0 metadata=1.2 UUID=5e60b492:1adc87ee:8e9a341d:df94a8da name=my-server:0
ARRAY /dev/md/1 metadata=1.2 UUID=799d1457:5131d974:1ca3384e:ce9e9e77 name=my-server:1
# This file was auto-generated on Wed, 11 Sep 2013 14:33:45 +0200
# by mkconf $Id$
DEVICE /dev/sdc1 /dev/sdd1
ARRAY /dev/md2 level=raid1 devices=/dev/sdc1,/dev/sdd1

To:
ARRAY /dev/md/0 metadata=1.2 UUID=5e60b492:1adc87ee:8e9a341d:df94a8da name=my-server:0
ARRAY /dev/md/1 metadata=1.2 UUID=799d1457:5131d974:1ca3384e:ce9e9e77 name=my-server:1
ARRAY /dev/md/2 metadata=1.2 UUID=563e2286:2f0115a0:bc92cb19:3383af19 name=my-server:2

That is I changed the configuration of the 3rd raid using the UUID of the disks.
To get the UUID of the disks, I used sudo blkid. sdc1 and sdd1 had the following values:
/dev/sdc1: UUID="563e2286-2f01-15a0-bc92-cb193383af19" UUID_SUB="6ec201e5-eaa4-3309-054e-8ec96c26da49" LABEL="my-server:2" TYPE="linux_raid_member"
/dev/sdd1: UUID="563e2286-2f01-15a0-bc92-cb193383af19" UUID_SUB="722bad2f-37f4-3c8e-5619-ca413c9d0b82" LABEL="my-server:2" TYPE="linux_raid_member"

That is, I used for the UUID of the raid md2 the UUID of sdc1 & sdd1 and
their label my-server:2. Note that the UUID of sdc1 & sdd1 and label are
the same but and the only difference is the UUID_SUB.

3. I changed /etc/fstab removing the entry related to md2 and replaced with one using UUID:
UUID=0ae06695-1a89-4c05-af34-68465224a71c       /mnt/raid       ext4    defaults0       0

4. I issued a "sudo update-initramfs -u"

5. reboot.
It worked for me. I think there are some issues when not using the UUID values.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to mdadm in Ubuntu.
https://bugs.launchpad.net/bugs/990913

Title:
  RAID goes into degrade mode on every boot 12.04 LTS server

Status in “mdadm” package in Ubuntu:
  Confirmed

Bug description:
  I have 2 new Dell PowerEdge R515.
  Box have 2 internal SAS drives and 12 hot swap
  I create a 12 driver raid 6 array on the 12 hot swap drives
  without problem but on every reboot I get a message about 
  either degraded or not enough drives for the raid 6.

  If I shutdown and pull all 12 drives and let boot. Then plug them in.
  The array comes up fine most everytime.

  This happens on both of these new R512

  Also loaded 12.04 LTS server on a R710 and
  the mpt2sas load and times out. I had to
  add rootdelay=180 to boot parms.

  Description:    Ubuntu 12.04 LTS
  Release:        12.04

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/990913/+subscriptions