I have a RAID 1 array:
# mdadm --detail /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Thu Oct 18 21:52:43 2012
Raid Level : raid1
Array Size : 1048564 (1024.16 MiB 1073.73 MB)
Used Dev Size : 1048564 (1024.16 MiB 1073.73 MB)
Raid Devices : 2
Total Devices : 3
Persistence : Superblock is persistent
Update Time : Fri Oct 19 16:25:32 2012
State : clean
Active Devices : 2
Working Devices : 3
Failed Devices : 0
Spare Devices : 1
Name : cow:0 (local to host cow)
UUID : 9e691db1:f8fcc7d8:f56d9c11:1c202693
Events : 98
Number Major Minor RaidDevice State
2 8 2 0 active sync /dev/sda2
3 8 18 1 active sync /dev/sdb2
4 8 34 - spare /dev/sdc2
Is it possible to change the numbers in the Number column to 0, 1, 2 instead of 2, 3, 4? They were 0, 1, 2 until I messed around a bit with the array, removing and adding devices.