software raid

[C M Reinehr]

Vu,

On Thu 07 August 2008 10:29, vu pham wrote:
> My RHEL5 server has the root partition mounted on  a software raid 5 of
> 3 disks sda, sdb and sdc. I remove one of the disks and mdadm still
> reports everything is ok, all disks are active and sync.
>
> The server hardware log does show the disk is removed. ( I checked this
> just in case I took the drive from another server ).
>
> Below is the output of mdadm.
>
> Thanks for your advice.
>
> Vu
>
>
> [root at wks-178 ~]# mount
> /dev/md2 on / type ext3 (rw)
> proc on /proc type proc (rw)
> sysfs on /sys type sysfs (rw)
> devpts on /dev/pts type devpts (rw,gid=5,mode=620)
> /dev/md0 on /boot type ext3 (rw)
> tmpfs on /dev/shm type tmpfs (rw)
> none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
> sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
>
> [root at wks-178 ~]# mdadm --detail /dev/md2
> /dev/md2:
>          Version : 00.90.03
>    Creation Time : Thu Aug  7 10:50:37 2008
>       Raid Level : raid0
>       Array Size : 421585152 (402.05 GiB 431.70 GB)
>     Raid Devices : 3
>    Total Devices : 3
> Preferred Minor : 2
>      Persistence : Superblock is persistent
>
>      Update Time : Thu Aug  7 10:50:37 2008
>            State : clean
>   Active Devices : 3
> Working Devices : 3
>   Failed Devices : 0
>    Spare Devices : 0
>
>       Chunk Size : 256K
>
>             UUID : cf7cc365:fbacd375:3a623d90:e9c8d292
>           Events : 0.1
>
>      Number   Major   Minor   RaidDevice State
>         0       8        3        0      active sync   /dev/sda3
>         1       8       19        1      active sync   /dev/sdb3
>         2       8       35        2      active sync   /dev/sdc3
> [root at wks-178 ~]#

I'm not sure that this answers your question, but the first thing I noticed is 
that your array is not raid 5, but rather is raid 0. I still would have 
imagined that mdadm would report a degraded array, but just for the record, 
you DO NOT have data redundancy with raid 0. You might want to reinstall that 
third drive.

HTH

cmr
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Debian 'Etch' - Registered Linux User #241964
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