![如何在 raid5 上恢复文件系统(ext4)?](https://linux22.com/image/778261/%E5%A6%82%E4%BD%95%E5%9C%A8%20raid5%20%E4%B8%8A%E6%81%A2%E5%A4%8D%E6%96%87%E4%BB%B6%E7%B3%BB%E7%BB%9F%EF%BC%88ext4%EF%BC%89%EF%BC%9F.png)
我在 raid5 阵列上有一个 ext4 文件系统,/dev/md0
由 mdadm 构建。
我发现重启一次后它没有被挂载。然后我运行了fcsk
它,但得到了一个超级块错误。
于是我打算运行一下mke2fs -n /dev/md0
获取备份超级块的信息。但我mke2fs /dev/md0
错误地运行了。第一次运行的时候,系统要求我输入一些关于日志的信息,而我按下了 Ctrl-C。但我还记得系统说写入了 inode 表。
此后,mke2fs -S /dev/md0
由于无法从备份中恢复它,我再次运行以生成超级块。
现在,超级块问题消失了,但 fsck 想要修复大量 inode 问题。我对其中一些问题回答是,然后按下 Ctrl-C,这时我意识到它似乎试图将 inode 修复到全新的 inode 表中。
我还能恢复所有数据吗?如果可以,该怎么做?
以下是突袭信息:
$ sudo mdadm -D /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Mon Jun 27 18:02:54 2022
Raid Level : raid5
Array Size : 7813707776 (7451.73 GiB 8001.24 GB)
Used Dev Size : 3906853888 (3725.87 GiB 4000.62 GB)
Raid Devices : 3
Total Devices : 3
Persistence : Superblock is persistent
Intent Bitmap : Internal
Update Time : Mon Jun 27 20:20:25 2022
State : clean, degraded, recovering
Active Devices : 2
Working Devices : 3
Failed Devices : 0
Spare Devices : 1
Layout : left-symmetric
Chunk Size : 64K
Consistency Policy : bitmap
Rebuild Status : 2% complete
Name : plq-pi:0 (local to host plq-pi)
UUID : a2250592:81ebb835:4646cf4f:64feea42
Events : 854
Number Major Minor RaidDevice State
0 8 33 0 active sync /dev/sdc1
1 8 17 1 active sync /dev/sdb1
3 254 0 2 spare rebuilding /dev/dm-0
$ cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 dm-0[3] sdb1[1] sdc1[0]
7813707776 blocks super 1.2 level 5, 64k chunk, algorithm 2 [3/2] [UU_]
[>....................] recovery = 2.0% (79757168/3906853888) finish=6664.4min speed=9570K/sec
bitmap: 0/30 pages [0KB], 65536KB chunk
unused devices: <none>
是/dev/dm-0
一个由两块磁盘构成的lvm。
我执行的命令:
$ sudo fsck /dev/md0
fsck from util-linux 2.33.1
e2fsck 1.44.5 (15-Dec-2018)
ext2fs_open2: Bad magic number in super-block
fsck.ext4: Superblock invalid, trying backup blocks...
fsck.ext4: Bad magic number in super-block while trying to open /dev/md0
The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem. If the device is valid and it really contains an ext2/ext3/ext4
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>
or
e2fsck -b 32768 <device>
$ sudo mkfs.ext4 /dev/md0
mke2fs 1.44.5 (15-Dec-2018)
Creating filesystem with 1835008000 4k blocks and 229376000 inodes
Filesystem UUID: cca2e089-18bf-4d19-a5c2-077b47304fd2
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Allocating group tables: done
Writing inode tables: done
Creating journal (262144 blocks): ^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C
$ sudo mkfs.ext4 -n /dev/md0
mke2fs 1.44.5 (15-Dec-2018)
Creating filesystem with 1835008000 4k blocks and 229376000 inodes
Filesystem UUID: 722ca4ca-1cf7-4860-baff-91a019258b3f
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
$ sudo e2fsck -b 1934917632 /dev/md0
e2fsck 1.44.5 (15-Dec-2018)
e2fsck: Invalid argument while trying to open /dev/md0
The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem. If the device is valid and it really contains an ext2/ext3/ext4
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>
or
e2fsck -b 32768 <device>
$ sudo e2fsck /dev/md0
e2fsck 1.44.5 (15-Dec-2018)
/dev/md0 contains a file system with errors, check forced.
Resize inode not valid. Recreate<y>? yes
Pass 1: Checking inodes, blocks, and sizes
Inode 1 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Root inode is not a directory. Clear<y>? yes
Inode 17 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 33 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 49 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 65 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 81 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 97 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 113 has EXTENTS_FL flag set on filesystem without extents support.
Clear ('a' enables 'yes' to all) <y>? yes
yyyyyyInode 129 has EXTENTS_FL flag set on filesystem without extents support.
Clear ('a' enables 'yes' to all) <y>? yes
Inode 145 has EXTENTS_FL flag set on filesystem without extents support.
Clear ('a' enables 'yes' to all) <y>? yes
Inode 161 has EXTENTS_FL flag set on filesystem without extents support.
Clear ('a' enables 'yes' to all) <y>? yes
Inode 177 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 193 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 209 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes
Inode 225 has EXTENTS_FL flag set on filesystem without extents support.
Clear<y>? yes to all
Inode 497 has EXTENTS_FL flag set on filesystem without extents support.
Clear? yes
... more these ...
Inode 4840 is in use, but has dtime set. Fix? yes
Inode 4840 has a extra size (6436) which is invalid
Fix? yes
Timestamp(s) on inode 4840 beyond 2310-04-04 are likely pre-1970.
Fix? yes
^CInode 4840 has a bad extended attribute block 1879399463. Clear? yes
/dev/md0: e2fsck canceled.
/dev/md0: ***** FILE SYSTEM WAS MODIFIED *****
/dev/md0: ********** WARNING: Filesystem still has errors **********
$ sudo e2fsck -f /dev/md0
e2fsck 1.44.5 (15-Dec-2018)
Resize inode not valid. Recreate<y>? yes
Pass 1: Checking inodes, blocks, and sizes
Root inode is not a directory. Clear<y>?
/dev/md0: e2fsck canceled.
/dev/md0: ***** FILE SYSTEM WAS MODIFIED *****
/dev/md0: ********** WARNING: Filesystem still has errors **********