我在我的家用服务器上运行了3个磁盘的Raid5。 但是在磁盘的背板上有一些问题。 磁盘没有被检测到可靠。 所以我更换了背板，现在检测到磁盘正确。 但是Md数组很奇怪。
当我用mdadm -Q /dev/sdX查询物理磁盘时，我得到：
root@omv:/etc/mdadm# mdadm -Q /dev/sdb /dev/sdb: is not an md array /dev/sdb: device 3 in 3 device unknown raid5 array. Use mdadm --examine for more detail. root@omv:/etc/mdadm# mdadm -Q /dev/sdc /dev/sdc: is not an md array /dev/sdc: device 0 in 3 device unknown raid5 array. Use mdadm --examine for more detail. root@omv:/etc/mdadm# mdadm -Q /dev/sdd /dev/sdd: is not an md array /dev/sdd: device 3 in 3 device unknown raid5 array. Use mdadm --examine for more detail.
然后用mdadm --examine /dev/sdX来获取更多的信息给我：
/dev/sdb: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : abdf672e:cf99b72d:df8be434:4b1320a7 Name : omv:pool (local to host omv) Creation Time : Thu Oct 20 23:09:18 2011 Raid Level : raid5 Raid Devices : 3 Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB) Array Size : 7814051840 (3726.03 GiB 4000.79 GB) Used Dev Size : 3907025920 (1863.02 GiB 2000.40 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : b08f4b42:3d5d774b:46dd4460:10162e23 Update Time : Tue Mar 27 20:47:45 2012 Checksum : 93cc85d - correct Events : 0 Layout : left-symmetric Chunk Size : 512K Device Role : spare Array State : A.. ('A' == active, '.' == missing) /dev/sdc: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : abdf672e:cf99b72d:df8be434:4b1320a7 Name : omv:pool (local to host omv) Creation Time : Thu Oct 20 23:09:18 2011 Raid Level : raid5 Raid Devices : 3 Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB) Array Size : 7814051840 (3726.03 GiB 4000.79 GB) Used Dev Size : 3907025920 (1863.02 GiB 2000.40 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : 3a5f2e45:a00ffef6:f1881208:258c62d6 Update Time : Tue Mar 27 20:47:45 2012 Checksum : 12a86cfe - correct Events : 246 Layout : left-symmetric Chunk Size : 512K Device Role : Active device 0 Array State : A.. ('A' == active, '.' == missing) /dev/sdd: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : abdf672e:cf99b72d:df8be434:4b1320a7 Name : omv:pool (local to host omv) Creation Time : Thu Oct 20 23:09:18 2011 Raid Level : raid5 Raid Devices : 3 Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB) Array Size : 7814051840 (3726.03 GiB 4000.79 GB) Used Dev Size : 3907025920 (1863.02 GiB 2000.40 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : d67e800b:e5372705:556cf02d:534eb1f5 Update Time : Tue Mar 27 20:47:45 2012 Checksum : 2c50597d - correct Events : 0 Layout : left-symmetric Chunk Size : 512K Device Role : spare Array State : A.. ('A' == active, '.' == missing)
如您所见，三个磁盘中的两个被标记为备用设备。 Mdstat显示了这一点：
cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md127 : inactive sdc[0](S) sdd[3](S) 3907027120 blocks super 1.2 unused devices: <none>
运行数组会产生以下错误：
mdadm: failed to run array /dev/md127: Input/output error
我也尝试手动组装数组，它告诉我，它不能创build两个磁盘的数组。 有没有办法强制磁盘的备用/活动状态，并改变arrays中的磁盘号码？