mdadm停止重build一个RAID5arrays99.9％

我最近在QNAP TS-412 NAS上安装了三个新磁盘。

这三个新磁盘应该与已经存在的磁盘组合成一个4磁盘RAID5arrays，所以我开始了迁移过程。

经过多次尝试（每次约24小时），迁移似乎工作，但导致了一个没有响应的NAS。

此时我重置NAS。 一切都从那里走下坡路：

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• NAS引导，但标记第一个磁盘失败，并从所有arrays中删除它，让他们跛行。
• 我在磁盘上运行检查，无法find任何问题（这将是奇怪的，因为它几乎是新的）。
• pipe理界面没有提供任何恢复选项，所以我想我只是手动做。

我已经使用mdadm （正在/dev/md4 ， /dev/md13和/dev/md9 ）成功重build所有QNAP内部RAID1arrays，只留下RAID5arrays; /dev/md0 ：

我已经使用这些命令多次尝试了这些命令：

 mdadm -w /dev/md0 

（必须在从/dev/sda3删除/dev/sda3之后，由NAS以只读方式挂载arrays，不能在RO模式下修改arrays）。

 mdadm /dev/md0 --re-add /dev/sda3 

之后arrays开始重build。 尽pipe这个系统的速度非常缓慢和/或没有响应，但它的速度却达到了99.9％。 （大多数情况下，使用SSHlogin失败）。

事物的当前状态：

 [admin@nas01 ~]# cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] md4 : active raid1 sdd2[2](S) sdc2[1] sdb2[0] 530048 blocks [2/2] [UU] md0 : active raid5 sda3[4] sdd3[3] sdc3[2] sdb3[1] 8786092608 blocks super 1.0 level 5, 64k chunk, algorithm 2 [4/3] [_UUU] [===================>.] recovery = 99.9% (2928697160/2928697536) finish=0.0min speed=110K/sec md13 : active raid1 sda4[0] sdb4[1] sdd4[3] sdc4[2] 458880 blocks [4/4] [UUUU] bitmap: 0/57 pages [0KB], 4KB chunk md9 : active raid1 sda1[0] sdd1[3] sdc1[2] sdb1[1] 530048 blocks [4/4] [UUUU] bitmap: 2/65 pages [8KB], 4KB chunk unused devices: <none> 

（现在停滞在2928697160/2928697536几小时）

 [admin@nas01 ~]# mdadm -D /dev/md0 /dev/md0: Version : 01.00.03 Creation Time : Thu Jan 10 23:35:00 2013 Raid Level : raid5 Array Size : 8786092608 (8379.07 GiB 8996.96 GB) Used Dev Size : 2928697536 (2793.02 GiB 2998.99 GB) Raid Devices : 4 Total Devices : 4 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Mon Jan 14 09:54:51 2013 State : clean, degraded, recovering Active Devices : 3 Working Devices : 4 Failed Devices : 0 Spare Devices : 1 Layout : left-symmetric Chunk Size : 64K Rebuild Status : 99% complete Name : 3 UUID : 0c43bf7b:282339e8:6c730d6b:98bc3b95 Events : 34111 Number Major Minor RaidDevice State 4 8 3 0 spare rebuilding /dev/sda3 1 8 19 1 active sync /dev/sdb3 2 8 35 2 active sync /dev/sdc3 3 8 51 3 active sync /dev/sdd3 

在检查/mnt/HDA_ROOT/.logs/kmsg ，事实certificate实际问题似乎是用/dev/sdb3代替的：

 <6>[71052.730000] sd 3:0:0:0: [sdb] Unhandled sense code <6>[71052.730000] sd 3:0:0:0: [sdb] Result: hostbyte=0x00 driverbyte=0x08 <6>[71052.730000] sd 3:0:0:0: [sdb] Sense Key : 0x3 [current] [descriptor] <4>[71052.730000] Descriptor sense data with sense descriptors (in hex): <6>[71052.730000] 72 03 00 00 00 00 00 0c 00 0a 80 00 00 00 00 01 <6>[71052.730000] 5d 3e d9 c8 <6>[71052.730000] sd 3:0:0:0: [sdb] ASC=0x0 ASCQ=0x0 <6>[71052.730000] sd 3:0:0:0: [sdb] CDB: cdb[0]=0x88: 88 00 00 00 00 01 5d 3e d9 c8 00 00 00 c0 00 00 <3>[71052.730000] end_request: I/O error, dev sdb, sector 5859367368 <4>[71052.730000] raid5_end_read_request: 27 callbacks suppressed <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246784 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246792 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246800 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246808 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246816 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246824 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246832 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246840 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246848 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5:md0: read error not correctable (sector 5857246856 on sdb3). <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. <4>[71052.730000] raid5: some error occurred in a active device:1 of md0. 

对于585724XXXX范围内的各个（随机）扇区，上述顺序以稳定的速率重复。

我的问题是：

• 为什么它会如此接近尾声，而仍然使用如此多的资源以致系统停滞（ md0_raid5和md0_resync进程仍在运行）。
• 有什么方法可以查看是什么导致它失败/失速？ < – 可能是由于sdb3错误。
• 我怎样才能完成操作而不会丢失我的3TB数据？ （像跳过sdb3上的麻烦部门，但保持完整的数据？）