Linux LVM逻辑卷错误恢复一例
XPZ0 2011-04-16
使用LVM建立了一个逻辑卷为/dev/mapper/test-test。
由于异常关机，造了逻辑卷错误，无法挂载。
于是检查逻辑卷，提示：
# fsck.ext3 -f /dev/mapper/test-test
e2fsck 1.38 (30-Jun-2005)
fsck.ext3: Attempt to read block from filesystem resulted in short read while trying to open /dev/mapper/test-test
Could this be a zero-length partition?
然后，查看了一下这个逻辑卷的信息：
# mkfs.ext3 -n /dev/mapper/test-test
mke2fs 1.38 (30-Jun-2005)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
6553600 inodes, 13107200 blocks
655360 blocks (5.00%) reserved for the super user
First data block=0
400 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424
然后，尝试了一下，用备用超级块来修复：
# fsck.ext3 -b 163840 /dev/mapper/test-test
e2fsck 1.38 (30-Jun-2005)
fsck.ext3: Attempt to read block from filesystem resulted in short read while trying to open /dev/mapper/test-test
Could this be a zero-length partition?
结果仍然报错。那就再试试重启lvm服务吧，执行
/etc/init.d/lvm stop
/etc/init.d/lvm start
然后再执行：
# fsck.ext3 -b 163840 /dev/mapper/test-test
e2fsck 1.38 (30-Jun-2005)
ext3 recovery flag is clear, but journal has data.
Recovery flag not set in backup superblock, so running journal anyway.
/dev/mapper/test-test: recovering journal
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/mapper/test-test: ***** FILE SYSTEM WAS MODIFIED *****
/dev/mapper/test-test: 31/6553600 files (3.2% non-contiguous), 1823265/13107200 blocks
执行/etc/init.d/checkfs.sh start，也可检查、修复文件系统。
