[mythtv-users] mdadm help, please

[John Drescher]

On Thu, Apr 23, 2009 at 11:46 PM, Joel Means <means.joel at gmail.com> wrote:
> I seem to be having major issues with my primary storage for all of my
> recordings and rips.  I am running Debian Lenny with a 2.6.29 kernel,
> compiled myself.  I have a seven disk RAID5.  My problem is that when I
> assemble my array, the array size shown is too small.  Here is what I get
> from mdadm -D /dev/md0:
>
> /dev/md0:
>         Version : 00.90
>   Creation Time : Thu Apr 23 21:25:14 2009
>      Raid Level : raid5
>      Array Size : 782819968 (746.56 GiB 801.61 GB)
>   Used Dev Size : 488383936 (465.76 GiB 500.11 GB)
>    Raid Devices : 7
>   Total Devices : 7
> Preferred Minor : 0
>     Persistence : Superblock is persistent
>
>     Update Time : Thu Apr 23 21:25:14 2009
>           State : clean, degraded
>  Active Devices : 6
> Working Devices : 7
>  Failed Devices : 0
>   Spare Devices : 1
>
>          Layout : left-symmetric
>      Chunk Size : 64K
>
>            UUID : 16b9b60d:ab7eb6b3:4bb6d167:00581514 (local to host
> meansnet.homelinux.org)
>          Events : 0.1
>
>     Number   Major   Minor   RaidDevice State
>        0       8       33        0      active sync   /dev/sdc1
>        1       8       97        1      active sync   /dev/sdg1
>        2       8       65        2      active sync   /dev/sde1
>        3       8       49        3      active sync   /dev/sdd1
>        4       8        1        4      active sync   /dev/sda1
>        5       8       81        5      active sync   /dev/sdf1
>        6       0        0        6      removed
>
>        7       8       17        -      spare   /dev/sdb1
>
>
> Using mdadm -E on each of the drives gives the correct info:
>
> /dev/sda1:
>           Magic : a92b4efc
>         Version : 00.90.00
>            UUID : 16b9b60d:ab7eb6b3:4bb6d167:00581514 (local to host
> meansnet.homelinux.org)
>   Creation Time : Thu Apr 23 21:25:14 2009
>      Raid Level : raid5
>   Used Dev Size : 488383936 (465.76 GiB 500.11 GB)
>      Array Size : 2930303616 (2794.56 GiB 3000.63 GB)
>    Raid Devices : 7
>   Total Devices : 8
> Preferred Minor : 0
>
>     Update Time : Thu Apr 23 21:25:14 2009
>           State : clean
>  Active Devices : 6
> Working Devices : 7
>  Failed Devices : 1
>   Spare Devices : 1
>        Checksum : 68722cb1 - correct
>          Events : 1
>
>          Layout : left-symmetric
>      Chunk Size : 64K
>
>       Number   Major   Minor   RaidDevice State
> this     4       8        1        4      active sync   /dev/sda1
>
>    0     0       8       33        0      active sync   /dev/sdc1
>    1     1       8       97        1      active sync   /dev/sdg1
>    2     2       8       65        2      active sync   /dev/sde1
>    3     3       8       49        3      active sync   /dev/sdd1
>    4     4       8        1        4      active sync   /dev/sda1
>    5     5       8       81        5      active sync   /dev/sdf1
>    6     6       0        0        6      faulty
>    7     7       8       17        7      spare   /dev/sdb1
>
>
> Note the difference in Array Size.  I can remove and re-add /dev/sdb1, and
> te array will start rebuilding, but the info from 'mdadm -E' doesn't
> change.  Running 'fsck.jfs' on /dev/md0 gives me an error about corrupt
> superblocks, so I don't know if my data is hosed or not.  This was working
> fine for over a year.   It could be the upgrade to the new kernel that did
> this, but trying to revert to the older kernel gave me several other
> issues,  Does anyone have any thoughts on what might be done to fix this?
> Or can you point me to where I might find more mdadm experts?  Thanks.
>

Can you post the output of cat /proc/mdstat?

How did you assemble the array? With the force option? And no you
array probably is not hosed although I am worried why the spare is not
being added automatically.

Is the output of

sfdisk -d /dev/sda

the same as all other disks?

Do you have mdadm 2.6.4 or greater installed?


John



John