如何重新组装（或从中恢复数据）mdadm RAID5arrays？

我试图从一个失败的NAS的RAID5arrays中恢复任何数据。

这些磁盘被物理地移动到另一台服务器，以便它们可以被映像，但Knoppix在启动时“有用地”检测并恢复了arrays： –

[ 677.791667] md: md0 stopped. [ 677.793443] md: bind<sdb> [ 677.793580] md: bind<sdc> [ 677.793866] md: bind<sdd> [ 677.794004] md: bind<sda> [ 678.671014] md: raid6 personality registered for level 6 [ 678.671017] md: raid5 personality registered for level 5 [ 678.671019] md: raid4 personality registered for level 4 [ 678.671446] md/raid:md0: device sda operational as raid disk 0 [ 678.671449] md/raid:md0: device sdc operational as raid disk 2 [ 678.671452] md/raid:md0: device sdb operational as raid disk 1 [ 678.671840] md/raid:md0: allocated 4222kB [ 678.671874] md/raid:md0: raid level 5 active with 3 out of 4 devices, algorithm 2 [ 678.671877] RAID conf printout: [ 678.671879] --- level:5 rd:4 wd:3 [ 678.671881] disk 0, o:1, dev:sda [ 678.671883] disk 1, o:1, dev:sdb [ 678.671886] disk 2, o:1, dev:sdc [ 678.671888] disk 3, o:1, dev:sdd [ 678.671923] md0: detected capacity change from 0 to 4500901330944 ^ RAID conf printout repeated ^ RAID conf printout repeated [ 678.679071] md: recovery of RAID array md0 [ 678.679074] md: minimum _guaranteed_ speed: 1000 KB/sec/disk. [ 678.679077] md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for recovery. [ 678.679083] md: using 128k window, over a total of 1465137152 blocks. [ 678.679086] md: resuming recovery of md0 from checkpoint. [ 678.694387] md0: unknown partition table [18209.608703] md: md0: recovery done [18209.690600] RAID conf printout: [18209.690605] --- level:5 rd:4 wd:4 [18209.690607] disk 0, o:1, dev:sda [18209.690610] disk 1, o:1, dev:sdb [18209.690612] disk 2, o:1, dev:sdc [18209.690614] disk 3, o:1, dev:sdd

之后，arrays看起来很健康，用/proc/mdstat显示： –

 Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sda[0] sdd[4] sdc[2] sdb[1] 4395411456 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/4] [UUUU]

但是，我无法直接挂载/dev/md0或find任何逻辑卷。

使用dd来提取/dev/md0的前512个字节会得到数组中的文件的部分内容，而不是MBR，所以我怀疑这是因为数组按错误顺序组装的。

如果正确，我该如何重新组装数组？

如果没有，尝试从arrays恢复数据的最佳方法是什么？

mdadm -D / dev / md0

 /dev/md0: Version : 1.2 Creation Time : Sun Aug 7 17:25:36 2011 Raid Level : raid5 Array Size : 4395411456 (4191.79 GiB 4500.90 GB) Used Dev Size : 1465137152 (1397.26 GiB 1500.30 GB) Raid Devices : 4 Total Devices : 4 Persistence : Superblock is persistent Update Time : Fri Aug 12 21:54:53 2011 State : clean Active Devices : 4 Working Devices : 4 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Name : Microknoppix:1 (local to host Microknoppix) UUID : 37b79cab:d800da6a:eec72e0d:6547b6ef Events : 19 Number Major Minor RaidDevice State 0 8 0 0 active sync /dev/sda 1 8 16 1 active sync /dev/sdb 2 8 32 2 active sync /dev/sdc 4 8 48 3 active sync /dev/sdd

mdadm -E / dev / sd？

 /dev/sda: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : 37b79cab:d800da6a:eec72e0d:6547b6ef Name : Microknoppix:1 (local to host Microknoppix) Creation Time : Sun Aug 7 17:25:36 2011 Raid Level : raid5 Raid Devices : 4 Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB) Array Size : 8790822912 (4191.79 GiB 4500.90 GB) Used Dev Size : 2930274304 (1397.26 GiB 1500.30 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : 42c9006b:1405120d:edf4d6da:e707f2dd Update Time : Mon Aug 15 02:19:35 2011 Checksum : 40b694de - correct Events : 19 Layout : left-symmetric Chunk Size : 512K Device Role : Active device 0 Array State : AAAA ('A' == active, '.' == missing) /dev/sdb: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : 37b79cab:d800da6a:eec72e0d:6547b6ef Name : Microknoppix:1 (local to host Microknoppix) Creation Time : Sun Aug 7 17:25:36 2011 Raid Level : raid5 Raid Devices : 4 Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB) Array Size : 8790822912 (4191.79 GiB 4500.90 GB) Used Dev Size : 2930274304 (1397.26 GiB 1500.30 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : 39fc5928:11ecb5b6:c3c088e6:2833b7ea Update Time : Mon Aug 15 02:19:35 2011 Checksum : c02aa5ea - correct Events : 19 Layout : left-symmetric Chunk Size : 512K Device Role : Active device 1 Array State : AAAA ('A' == active, '.' == missing) /dev/sdc: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : 37b79cab:d800da6a:eec72e0d:6547b6ef Name : Microknoppix:1 (local to host Microknoppix) Creation Time : Sun Aug 7 17:25:36 2011 Raid Level : raid5 Raid Devices : 4 Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB) Array Size : 8790822912 (4191.79 GiB 4500.90 GB) Used Dev Size : 2930274304 (1397.26 GiB 1500.30 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : 90c64aa7:82b06090:fe9363e1:380dc0da Update Time : Mon Aug 15 02:19:35 2011 Checksum : 3a9e1ff - correct Events : 19 Layout : left-symmetric Chunk Size : 512K Device Role : Active device 2 Array State : AAAA ('A' == active, '.' == missing) /dev/sdd: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : 37b79cab:d800da6a:eec72e0d:6547b6ef Name : Microknoppix:1 (local to host Microknoppix) Creation Time : Sun Aug 7 17:25:36 2011 Raid Level : raid5 Raid Devices : 4 Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB) Array Size : 8790822912 (4191.79 GiB 4500.90 GB) Used Dev Size : 2930274304 (1397.26 GiB 1500.30 GB) Data Offset : 2048 sectors Super Offset : 8 sectors State : clean Device UUID : fab3ec51:50f9bbc6:7ac51700:54195903 Update Time : Mon Aug 15 02:19:35 2011 Checksum : 2bf455cf - correct Events : 19 Layout : left-symmetric Chunk Size : 512K Device Role : Active device 3 Array State : AAAA ('A' == active, '.' == missing)

fdisk -l

 Disk /dev/sda: 1500.3 GB, 1500301910016 bytes 255 heads, 63 sectors/track, 182401 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x894e894e Device Boot Start End Blocks Id System /dev/sda1 1 267350 2147483647+ ee GPT Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes 255 heads, 63 sectors/track, 182401 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdb doesn't contain a valid partition table Disk /dev/sdc: 1500.3 GB, 1500301910016 bytes 255 heads, 63 sectors/track, 182401 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdc doesn't contain a valid partition table Disk /dev/sdd: 1500.3 GB, 1500301910016 bytes 255 heads, 63 sectors/track, 182401 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdd doesn't contain a valid partition table Disk /dev/md0: 4500.9 GB, 4500901330944 bytes 2 heads, 4 sectors/track, 1098852864 cylinders Units = cylinders of 8 * 512 = 4096 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 524288 bytes / 1572864 bytes Disk identifier: 0x312e312f Disk /dev/md0 doesn't contain a valid partition table

我发现很难相信mdadm会以错误的顺序组装驱动器。它的元数据不是那么糟糕。我想知道什么应该在RAIDarrays上，以及什么dmesg不得不说，当你尝试（和失败）安装arrays的事情。

如果你的猜测是正确的，那么arrays实际上乱序是正确的，我会拔下磁盘，放弃数据，或拨出专业数据恢复的地方，试图把它们放回去。有一个机会，你可以做到这一点，但也有一个机会，你会弄得一塌糊涂，使数据难以恢复的专业人士，以及你的时间值得基本上学习数据恢复飞？