https://raid.wiki.kernel.org/index.php/Mdstat says that the number shown in square brackets after each component device is the role number, but this does not appear to be true (at least not always): [root@c6 ~]# mdadm -C /dev/md0 -l 5 -n 3 -x 1 /dev/sd[bcde] mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md0 started. [root@c6 ~]# cat /proc/mdstat Personalities : [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid5 sdd[4] sde[3](S) sdc[1] sdb[0] 4191232 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU] [root@c6 ~]# mdadm --detail /dev/md0 /dev/md0: Version : 1.2 Creation Time : Mon Sep 23 10:54:59 2013 Raid Level : raid5 Array Size : 4191232 (4.00 GiB 4.29 GB) Used Dev Size : 2095616 (2046.84 MiB 2145.91 MB) Raid Devices : 3 Total Devices : 4 Persistence : Superblock is persistent Update Time : Mon Sep 23 10:56:13 2013 State : clean Active Devices : 3 Working Devices : 4 Failed Devices : 0 Spare Devices : 1 Layout : left-symmetric Chunk Size : 512K Name : c6.penurio.us:0 (local to host c6.penurio.us) UUID : 17b42cb3:691ea02a:1d9822a1:6be0b398 Events : 18 Number Major Minor RaidDevice State 0 8 16 0 active sync /dev/sdb 1 8 32 1 active sync /dev/sdc 4 8 48 2 active sync /dev/sdd 3 8 64 - spare /dev/sde Doc bug? -- ======================================================================== Ian Pilcher arequipeno@xxxxxxxxx Sometimes there's nothing left to do but crash and burn...or die trying. ======================================================================== -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
