我的外置磁盘柜与服务器之间的 SAS 电缆坏了，于是我换了一条新的。但是重新连接后，所有磁盘的标签都变了，例如 sdi --> sdu、sdj --> sdv 等。而且由这些磁盘组成的 RAID0 阵列也失效了。
更多详细信息：raid0 阵列是从 sd[ijklmnopqrst] 创建的。重新连接后，所有 12 个磁盘标签都已更改。我从 fdisk 收到的错误消息是fdisk: cannot open /dev/md126: Input/output error
输出cat /proc/mdstat：
Personalities : [raid0] [raid6] [raid5] [raid4]
md125 : active raid5 sdd[2] sdc[1] sdb[0]
11718486016 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU]
bitmap: 2/44 pages [8KB], 65536KB chunk
md126 : active raid0 sdj[0] sdi[9] sds[4] sdq[11] sdo[3] sdp[7] sdt[8] sdm[10] sdk[5] sdl[6] sdr[2] sdn[1]
46882646016 blocks super 1.2 512k chunks
md127 : active raid0 sdh[3] sdg[2] sdf[1] sde[0]
23436972032 blocks super 1.2 512k chunks
unused devices: <none>
输出lsblk：
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 5.5T 0 disk
├─sda1 8:1 0 200M 0 part /boot/efi
├─sda2 8:2 0 500M 0 part /boot
└─sda3 8:3 0 416G 0 part
├─centos-root 253:0 0 100G 0 lvm /
├─centos-swap 253:1 0 16G 0 lvm [SWAP]
├─centos-var 253:2 0 50G 0 lvm /var
└─centos-install 253:3 0 250G 0 lvm
sdb 8:16 0 5.5T 0 disk
└─md125 9:125 0 10.9T 0 raid5 /home
sdc 8:32 0 5.5T 0 disk
└─md125 9:125 0 10.9T 0 raid5 /home
sdd 8:48 0 5.5T 0 disk
└─md125 9:125 0 10.9T 0 raid5 /home
sde 8:64 0 5.5T 0 disk
└─md127 9:127 0 21.8T 0 raid0 /temp
sdf 8:80 0 5.5T 0 disk
└─md127 9:127 0 21.8T 0 raid0 /temp
sdg 8:96 0 5.5T 0 disk
└─md127 9:127 0 21.8T 0 raid0 /temp
sdh 8:112 0 5.5T 0 disk
└─md127 9:127 0 21.8T 0 raid0 /temp
sdu 65:64 0 3.7T 0 disk
sdv 65:80 0 3.7T 0 disk
sdw 65:96 0 3.7T 0 disk
sdx 65:112 0 3.7T 0 disk
sdy 65:128 0 3.7T 0 disk
sdz 65:144 0 3.7T 0 disk
sdaa 65:160 0 3.7T 0 disk
sdab 65:176 0 3.7T 0 disk
sdac 65:192 0 3.7T 0 disk
sdad 65:208 0 3.7T 0 disk
sdae 65:224 0 3.7T 0 disk
sdaf 65:240 0 3.7T 0 disk
在/etc/mdadm.conf（CentOS重启后将md1改为md126）：
ARRAY /dev/md0 UUID=a540f7c4-5839-4154-8399-42036a8664cf
ARRAY /dev/md1 UUID=759f63aa-b049-4e86-b4ce-c2391438807f
ARRAY /dev/md2 UUID=4ab4e822-9e63-41d0-a07b-daae3ea2bff7
ARRAY /dev/md0 UUID=a540f7c4-5839-4154-8399-42036a8664cf
ARRAY /dev/md1 UUID=759f63aa-b049-4e86-b4ce-c2391438807f
ARRAY /dev/md2 UUID=4ab4e822-9e63-41d0-a07b-daae3ea2bff7
mdadm -D /dev/md126以及（失败的 raid0）的输出：
/dev/md126:
Version : 1.2
Creation Time : Tue Apr 5 19:54:19 2016
Raid Level : raid0
Array Size : 46882646016 (44710.78 GiB 48007.83 GB)
Raid Devices : 12
Total Devices : 12
Persistence : Superblock is persistent
Update Time : Tue Apr 5 19:54:19 2016
State : clean
Active Devices : 12
Working Devices : 12
Failed Devices : 0
Spare Devices : 0
Chunk Size : 512K
Number Major Minor RaidDevice State
0 8 144 0 active sync
1 8 208 1 active sync
2 65 16 2 active sync
3 8 224 3 active sync
4 65 32 4 active sync
5 8 160 5 active sync
6 8 176 6 active sync
7 8 240 7 active sync
8 65 48 8 active sync
9 8 128 9 active sync
10 8 192 10 active sync
11 65 0 11 active sync
看来 12 盘 raid0 阵列仍然存在。以下是mdadm --examine /dev/sdu（以前在 md126 中）的输出：
/dev/sdu:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : fef2dd89:7ef6045d:0b671362:244393f4
Name : storage1.cluster.net:2
Creation Time : Tue Apr 5 19:54:19 2016
Raid Level : raid0
Raid Devices : 12
Avail Dev Size : 7813775024 (3725.90 GiB 4000.65 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
Unused Space : before=262056 sectors, after=0 sectors
State : clean
Device UUID : 82e28b37:5308ad64:ab0209d6:21b23484
Update Time : Tue Apr 5 19:54:19 2016
Bad Block Log : 512 entries available at offset 72 sectors
Checksum : 5d2d5658 - correct
Events : 0
Chunk Size : 512K
Device Role : Active device 9
Array State : AAAAAAAAAAAA ('A' == active, '.' == missing, 'R' == replacing)
错误消息来自dmesg | tail：
[3525097.349398] XFS (md126): xfs_log_force: error -5 returned.
[3525127.415308] XFS (md126): xfs_log_force: error -5 returned.
[3525157.481331] XFS (md126): xfs_log_force: error -5 returned.
[3525187.547243] XFS (md126): xfs_log_force: error -5 returned.
[3525217.613119] XFS (md126): xfs_log_force: error -5 returned.
[3525247.679038] XFS (md126): xfs_log_force: error -5 returned.
[3525277.744885] XFS (md126): xfs_log_force: error -5 returned.
[3525307.810813] XFS (md126): xfs_log_force: error -5 returned.
[3525337.876736] XFS (md126): xfs_log_force: error -5 returned.
[3525367.942628] XFS (md126): xfs_log_force: error -5 returned.
有没有什么方法可以恢复这些磁盘标签以及 RAID0 阵列而不丢失数据？
答案1
我只需重新启动系统即可解决问题。