[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Missing devices on raid1 setup

I have a raid1 setup with three partitions:

md0, mounted on /, composed of /dev/sda1 and /dev/sdb1
md1, mounted on swap, composed of /dev/sda2 and /dev/sdb2
md2, mounted on swap, composed of /dev/sda3 and /dev/sdb3

I am not sure how it was installed because it was done a long time ago, I 
don't even if I did it myself or someone else. I've found that the whole b 
disk was in removed state, so we put a new disk (just in case) and added it. 
Now when I reboot I get this state:

# mdadm --detail --scan
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda3,/dev/sdb3
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda1
ARRAY /dev/md1 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda2

As you can see md0 and m1 are missing the second member of the array. Further 
inquiring shows it is removed:

# mdadm --detail /dev/md0
/dev/md0:
        Version : 00.90.01
  Creation Time : Tue Feb  7 14:58:18 2006
     Raid Level : raid1
     Array Size : 15623104 (14.90 GiB 16.00 GB)
    Device Size : 15623104 (14.90 GiB 16.00 GB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Wed Feb 21 01:04:16 2007
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : a1a07d14:64ab7244:8a585e9b:fbee0505
         Events : 0.6120832

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       0        0        -      removed

# mdadm --detail /dev/md1
/dev/md1:
        Version : 00.90.01
  Creation Time : Tue Feb  7 14:59:06 2006
     Raid Level : raid1
     Array Size : 979840 (956.88 MiB 1003.36 MB)
    Device Size : 979840 (956.88 MiB 1003.36 MB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Wed Feb 21 00:43:44 2007
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : 2e8d1e91:1db84b53:602c6a7d:b9fb162a
         Events : 0.1409

    Number   Major   Minor   RaidDevice State
       0       8        2        0      active sync   /dev/sda2
       1       0        0        -      removed



I believe md2 was ok because it was actually assembled 
from /etc/mdadm/mdadm.conf which lists both partitions correctly:

# cat /etc/mdadm/mdadm.conf
DEVICE partitions
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md1 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda2,/dev/sdb2
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda3,/dev/sdb3

but md0 and md1 must have been assembled with another method (because there 
was no /etc at that time to read configs from) and that must be failing 
somehow.
The kernel command line is: root=/dev/md0 ro md=0,/dev/sda1,/dev/sdb1

The relevant information from dmesg is:

md: md driver 0.90.0 MAX_MD_DEVS=256, MD_SB_DISKS=27
md: raid1 personality registered as nr 3
...
md: raid0 personality registered as nr 2
raid5: automatically using best checksumming function: pIII_sse
   pIII_sse  :  5044.000 MB/sec
raid5: using function: pIII_sse (5044.000 MB/sec)
md: raid5 personality registered as nr 4
...
md: md1 stopped.
md: bind<sda2>
raid1: raid set md1 active with 1 out of 2 mirrors
md: md0 stopped.
md: bind<sda1>
raid1: raid set md0 active with 1 out of 2 mirrors
kjournald starting.  Commit interval 5 seconds
EXT3-fs: mounted filesystem with ordered data mode.
Adding 979832k swap on /dev/md1.  Priority:-1 extents:1
EXT3 FS on md0, internal journal
Capability LSM initialized
md: md2 stopped.
md: bind<sdb3>
md: bind<sda3>
raid1: raid set md2 active with 2 out of 2 mirrors
kjournald starting.  Commit interval 5 seconds
EXT3 FS on md2, internal journal
EXT3-fs: mounted filesystem with ordered data mode.


Any ideas what is wrong here?

If after that I add the spare partitions, everything is good, until the next 
reboot:

# mdadm /dev/md0 --add /dev/sdb1
mdadm: hot added /dev/sdb1
# mdadm /dev/md1 --add /dev/sdb2
mdadm: hot added /dev/sdb2

# mdadm --detail --scan
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda3,/dev/sdb3
ARRAY /dev/md0 level=raid1 num-devices=2 spares=1 UUID=[...]
   devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md1 level=raid1 num-devices=2 spares=1 UUID=[...]
   devices=/dev/sda2,/dev/sdb2

and after waiting some minutes:

ARRAY /dev/md2 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda3,/dev/sdb3
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md1 level=raid1 num-devices=2 UUID=[...]
   devices=/dev/sda2,/dev/sdb2

Any help is greatly appreciated.

Thank you.
-- 
José Pablo Fernández
pablo.fernandez@rs.com.ar
Reply to: