Soft RAID0 problems

I have inherited a preinstalled/configurred RHEL4 linux box with two soft RAID0 md0 and md1 with 3x400GB SATA drives in each. md1 keeps a snapshot of md0 with rsync done every night. This has been working fine for a couple of years but now md1 is showing problems. Some times md1 goes into read-only mode. I can remount it in RW mode but in a few days it goes into RO mode. I think that either one of the participating drive or SATA controller channel has a problem because I see kernel errors in syslog from drive sde but mdadm says the array is clean and ailed Devices: 0. Output of /etc/mdadm.conf /etc/fstab /var/log/messages /sbin/mdadm is attached. I have two questions:

a) How to get right information from mdadm utility (or any thing else) about health of the RAIDs?
b) All the 6 drives seem to be randomly connected to two 4-ports SATA controllers. How to identify which of the 6 drives is sde?

Thanks,
Vinod

# touch /mnt/cmb_bak/tst   #<---------------------------------
touch: cannot touch `/mnt/cmb_bak/tst': Read-only file system

# /etc/mdadm.conf   #<---------------------------------

DEVICE /dev/sd*
ARRAY /dev/md1 level=raid0 num-devices=3 UUID=8496dacc:5054fd06:676e8a5a:a70269fb
   devices=/dev/sdd1,/dev/sde1,/dev/sdf1
ARRAY /dev/md0 level=raid0 num-devices=3 UUID=efaa977d:01f27a1d:4d96e82c:141878c3
   devices=/dev/sda1,/dev/sdb1,/dev/sdc1


# grep /dev/md /etc/fstab   #<---------------------------------
/dev/md0                /mnt/cmb        ext3     data=writeback,noatime 1 2
/dev/md1                /mnt/cmb_bak    ext3     data=writeback,noatime 1 2

# df /dev/md0 /dev/md1
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/md0             1153734004 1013307300  81820396  93% /mnt/cmb
/dev/md1             1153734004 1013278608  81849088  93% /mnt/cmb_bak

/var/log/messages:   #<---------------------------------
Apr 26 12:29:12 ds5 kernel: Info fld=0x4000000 (nonstd), Invalid sde: sense = 72 11
Apr 26 12:29:12 ds5 kernel: end_request: I/O error, dev sde, sector 0
Apr 26 12:29:12 ds5 kernel: Buffer I/O error on device sde, logical block 0

# /sbin/mdadm --detail /dev/md1   #<---------------------------------
/dev/md1:
        Version : 00.90.01
  Creation Time : Wed May  3 14:55:57 2006
     Raid Level : raid0
     Array Size : 1172126208 (1117.83 GiB 1200.26 GB)
   Raid Devices : 3
  Total Devices : 3
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Wed May  3 14:55:57 2006
          State : clean
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

     Chunk Size : 64K

           UUID : 8496dacc:5054fd06:676e8a5a:a70269fb
         Events : 0.1

    Number   Major   Minor   RaidDevice State
       0       8       49        0      active sync   /dev/sdd1
       1       8       65        1      active sync   /dev/sde1
       2       8       81        2      active sync   /dev/sdf1

Start Free Trial