在线收缩扩展LVM

在安装系统时LVM的大小没有设定好，还好可以在线收缩和扩展。
1，看下各逻辑卷大小
[root@bogon ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       39G  461M   37G   2% /
/dev/mapper/VolGroup00-LogVol03
                       64G  222M   61G   1% /var
/dev/mapper/VolGroup00-LogVol02
                       49G  2.0G   45G   5% /usr
/dev/mapper/VolGroup00-LogVol01
                       39G  177M   37G   1% /home
/dev/sda1              99M   13M   82M  14% /boot
tmpfs                1005M     0 1005M   0% /dev/shm
/dev/hdc              3.5G  3.5G     0 100% /media
2，看到home下有lost+found可见home分区单独挂载在一个分区下
[root@bogon ~]# ls /home/
innofidei  lost+found
3，卸载并验证
[root@bogon ~]# umount /dev/mapper/VolGroup00-LogVol01
[root@bogon ~]# ls /home/
4，resize2fs  卷组先
[root@bogon ~]# resize2fs /dev/mapper/VolGroup00-LogVol01 20G
resize2fs 1.39 (29-May-2006)
Resizing the filesystem on /dev/mapper/VolGroup00-LogVol01 to 5242880 (4k) blocks.
The filesystem on /dev/mapper/VolGroup00-LogVol01 is now 5242880 blocks long.
注意这里会提醒你e2fsck的
所以resize2fs之前要这样做： e2fsck -f /dev/mapper/VolGroup-logVol01
5，减小lvm
[root@bogon ~]# lvreduce -L 20G /dev/mapper/VolGroup00-LogVol01
  /dev/hdc: open failed: Read-only file system
  WARNING: Reducing active logical volume to 20.00 GB
  THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce LogVol01? [y/n]: y
  Reducing logical volume LogVol01 to 20.00 GB
  Logical volume LogVol01 successfully resized
6,重新挂载并验证
[root@bogon ~]# mount -a
[root@bogon ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       39G  461M   37G   2% /
/dev/mapper/VolGroup00-LogVol03
                       64G  222M   61G   1% /var
/dev/mapper/VolGroup00-LogVol02
                       49G  2.0G   45G   5% /usr
/dev/sda1              99M   13M   82M  14% /boot
tmpfs                1005M     0 1005M   0% /dev/shm
/dev/hdc              3.5G  3.5G     0 100% /media
/dev/mapper/VolGroup00-LogVol01
                       20G  173M   19G   1% /home
[root@bogon ~]# ls /home/
innofidei  lost+found
7，扩展另一lvm
[root@bogon ~]# lvextend -L +20G /dev/mapper/VolGroup00-LogVol02
  /dev/hdc: open failed: Read-only file system
  Extending logical volume LogVol02 to 70.00 GB
  Logical volume LogVol02 successfully resized
[root@bogon ~]# resize2fs /dev/mapper/VolGroup00-LogVol02
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/mapper/VolGroup00-LogVol02 is mounted on /usr; on-line resizing required
Performing an on-line resize of /dev/mapper/VolGroup00-LogVol02 to 18350080 (4k) blocks.
The filesystem on /dev/mapper/VolGroup00-LogVol02 is now 18350080 blocks long.
8,再验证
[root@bogon ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       39G  461M   37G   2% /
/dev/mapper/VolGroup00-LogVol03
                       64G  222M   61G   1% /var
/dev/mapper/VolGroup00-LogVol02
                       68G  2.0G   63G   4% /usr
/dev/sda1              99M   13M   82M  14% /boot
tmpfs                1005M     0 1005M   0% /dev/shm
/dev/hdc              3.5G  3.5G     0 100% /media
/dev/mapper/VolGroup00-LogVol01
                       20G  173M   19G   1% /home