Hi,
I am new to this Forum,

we have SAN Storage attached to Server, with RAID-1 configuration with Software RAID.

from Terminal,

mdadm --detail /dev/md4

gives the ouput as:

Raid Devices : 2
Total Devices : 1
Preferred Minor : 4
persistence : Superblock is persistent

State : clean, no-errors
Active Devices : 1
Working Devices : 1
Failed Devices : 0
Spare devices : 0

Number Major Minor RaidDevice State
0 0 0 -1 removed
1 120 17 1 active sync /dev/emc1
UID : some number is written
Events : 0.821361


Like this in Many of the Servers atleast one mirrored device is showing "removed"

can someone give some hints to make it up.

I wonder what version of mdadm you are running, output is different from what I get.

What does cat /proc/mdstat yield?

jlinkels

Hi,

The version not correct, but in output window i have truncated some of the information.

and by the way from cat /proc/mdstat gives result as

md4 : active raid1 emcpowerb1[1]
104856128 blocks [2/1] [_U]

Please don't truncate in such cases, any information can give a pointer.

Anyway, it seems like your first disk in the array is not there. Either it is disconnected, not present or defect.

This line:
active raid1 emcpowerb1[1]
should read:
active raid1 emcpowerb1[0] emcpowerb1[1]
to mention the two partitions RAID consists of.
And this indicates a complete array:
104856128 blocks [2/1] [UU]

I am surprised with the partition name emcpowerb1. I have not seen such a naming before.

jlinkels