Monitoring Status With Mdadm - Novell LINUX ENTERPRISE SERVER 10 - STORAGE ADMINISTRATION GUIDE FOR EVMS Administration Manual

Status Information
Personalities : [raid5]
[raid4]
md0 : active
raid5
sdg1[0] sdk1[4] sdj1[3]
sdi1[2]
35535360 blocks level
5, 128k chunk,
algorithm 2 [5/4]
[U_UUU]
unused devices:
<none>

6.6.3 Monitoring Status with mdadm

To view the RAID status with the mdadm command, enter the following at a terminal prompt:
mdadm -D /dev/mdx
Replace mdx with the RAID device number.
Example 1: A Disk Fails
In the following example, only 4 of the 5 devices in the RAID are active (Raid Devices : 5,
Total Devices : 4). When it was created, the component devices in the device were
numbered 0 to 5 and are ordered according to their alphabetic appearance in the list where they were
chosen, such as /dev/sdg1, /dev/sdh1, /dev/sdi1, /dev/sdj1, and /dev/sdk1. From
the pattern of filenames of the other devices, you determine that the device that was removed was
named /dev/sdh1.
/dev/md0:
Description
List of the RAIDs on the server
by RAID label.
<device> : <active | not active>
<RAID label you specified>
< storage object> [RAID order]
<number of blocks> blocks
level < 0 | 1 | 4 | 5 >
<stripe size in KB> chunk
algorithm <1 | 2 | 3 | 4 >
[number of devices/number of
working devices]
[U-UUU]
All segments in the RAID are in
use.
Interpretation
You have two RAIDs defined
with labels of raid5 and
raid4.
The RAID is active and
mounted at /dev/evms/
md/md0.
The RAID label is raid5.
The active segments are sdg1,
sdi1, sdj1, and sdk1, as
ordered in the RAID.
The RAID numbering of 0 to 4
indicates that the RAID has 5
segments, and the second
segment [1] is missing from
the list. Based on the
segment names, the missing
segment is sdh1.
If the block size on the server is
4 KB, the total size of the
RAID (including parity) is
142 GB, with a data capacity
of 113.7 GB.
The stripe size is 128 KB.
The RAID is using left
symmetric.
algorithm <1 | 2 | 3 | 4 >
[number of devices/number of
working devices]
[U-UUU]
There are no spare devices
available on the server.
Managing Software RAIDs with EVMS 69