无法格式化分区的原因记录

无法格式化磁盘分区：

# mkfs.ext4 /dev/sdb1
mke2fs 1.41.12 (17-May-2010)
/dev/sdb1 is apparently in use by the system; will not make a filesystem

查看原因：

# dmsetup status
VG01-base: 0 4194304 linear  #/dev/sdb1设置为VG01之后被dm服务占用
VG01-test_wang: 0 11747328 linear
vg_infonix6-lv_swap: 0 4128768 linear
vg_infonix6-lv_root: 0 36782080 linear

# lvs
  LV      VG          Attr   LSize  Origin Snap%  Move Log Copy% Convert
  lv_root vg_infonix6 -wi-ao 17.54g
  lv_swap vg_infonix6 -wi-ao  1.97g

解决方法：

# dmsetup remove VG01-base
# dmsetup remove VG01-test_wang      #删除映射关系，即取消占用
# dmsetup status
vg_infonix6-lv_swap: 0 4128768 linear
vg_infonix6-lv_root: 0 36782080 linear

继续格式化分区：

# mkfs.ext4 /dev/sdb1     #以下是正常格式化过程
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
524288 inodes, 2097148 blocks
104857 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2147483648
64 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 39 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.