2006隨手札記

LAB

%Raid ( a disk fail)

1.create raid5

#mdadm -C /dev/md0 -l 5 -n 3 /dev/sdb{5,6,7}
#mkfs.ext3 /dev/md0
#cat /proc/mdstat

[root@server1 ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid0]
md1 : active raid0 sdb3[1] sdb2[0]
200192 blocks 64k chunks

2. a disk fail (dev/sdb5)

#mdadm --fail /dev/md0 /dev/sdb5

[root@server1 ~]# mdadm --fail /dev/md0 /dev/sdb5
mdadm: set /dev/sdb5 faulty in /dev/md0
[root@server1 ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid0]
md1 : active raid0 sdb3[1] sdb2[0]
200192 blocks 64k chunks

md0 : active raid5 sdb7[2] sdb6[1] sdb5[3](F)
200192 blocks level 5, 64k chunk, algorithm 2 [3/2] [_UU]

unused devices:

3. remove bad disk

#mdadm --remove /dev/md0 /dev/sdb5
#cat /proc/mdstat

[root@server1 ~]# mdadm --remove /dev/md0 /dev/sdb5
mdadm: hot removed /dev/sdb5
[root@server1 ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid0]
md1 : active raid0 sdb3[1] sdb2[0]
200192 blocks 64k chunks

md0 : active raid5 sdb7[2] sdb6[1]
200192 blocks level 5, 64k chunk, algorithm 2 [3/2] [_UU]

unused devices:

4. add a good disk

#mdadm -a /dev/md0 /dev/sdb5
#cat /proc/mdstat

[root@server1 ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid0]
md1 : active raid0 sdb3[1] sdb2[0]
200192 blocks 64k chunks

md0 : active raid5 sdb5[0] sdb7[2] sdb6[1]
200192 blocks level 5, 64k chunk, algorithm 2 [3/2] [_UU]
[=>...................] recovery = 9.1% (10144/100096) finish=0.8min speed=1690K/sec

unused devices:

(Raid5開始Recovery...)