Linux(CentOS6) 调整 /home 挂载 分区大小

安装centos6.3使用自动推荐分区，发现一个问题/home 分区过大，超过了1.1T。

[root@localhost ~]# df -h
文件系统              容量  已用  可用 已用%% 挂载点
/dev/mapper/VolGroup-lv_root
50G  2.9G   44G   7% /
tmpfs                 5.9G  100K  5.9G   1% /dev/shm
/dev/sda1             485M   37M  423M   8% /boot
/dev/mapper/VolGroup-lv_home
1.1T  200M  988G   1% /home

目标：/home分20G，剩下添加给/目录下。

1.查看分区模式

[root@localhost ~]# df -h
文件系统              容量  已用  可用 已用%% 挂载点
/dev/mapper/VolGroup-lv_root
50G  2.9G   44G   7% /
tmpfs                 5.9G  100K  5.9G   1% /dev/shm
/dev/sda1             485M   37M  423M   8% /boot
/dev/mapper/VolGroup-lv_home
1.1T  200M  988G   1% /home

2.卸载挂载分区

[root@localhost ~]# umount /home

3.检查VolGroup-lv_home文件的错误性，-f 即使文件系统没有错误迹象，仍强制地检查正确性。

[root@localhost ~]# e2fsck -f /dev/mapper/VolGroup-lv_home
e2fsck 1.41.12 (17-May-2010)
第一步: 检查inode,块,和大小
第二步: 检查目录结构
第3步: 检查目录连接性
Pass 4: Checking reference counts
第5步: 检查簇概要信息
/dev/mapper/VolGroup-lv_home: 27/69304320 files (0.0% non-contiguous), 4400705/277215232 blocks

4.调整/home为20G，

[root@localhost ~]# resize2fs -p /dev/mapper/VolGroup-lv_home 20G
resize2fs 1.41.12 (17-May-2010)
Resizing the filesystem on /dev/mapper/VolGroup-lv_home to 5242880 (4k) blocks.
Begin pass 2 (max = 32784)
正在重定位块            XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Begin pass 3 (max = 8460)
正在扫描inode表          XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Begin pass 4 (max = 15)
正在更新inode引用       XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
The filesystem on /dev/mapper/VolGroup-lv_home is now 5242880 blocks long.

5.重新挂载并查看

[root@localhost ~]# mount /home
[root@localhost ~]# df -h
文件系统              容量  已用  可用 已用%% 挂载点
/dev/mapper/VolGroup-lv_root
50G  2.9G   44G   7% /
tmpfs                 5.9G  100K  5.9G   1% /dev/shm
/dev/sda1             485M   37M  423M   8% /boot
/dev/mapper/VolGroup-lv_home
20G  172M   19G   1% /home

6.划分20G外面的剩余空间。使用lvreduce指令用于减少LVM逻辑卷占用的空间大小。可能会删除逻辑卷上已有的数据，所以在操作前必须进行确认。记得输入 “y”

[root@localhost ~]# lvreduce -L 20G /dev/mapper/VolGroup-lv_home
WARNING: Reducing active and open logical volume to 20.00 GiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce lv_home? [y/n]: y
Reducing logical volume lv_home to 20.00 GiB
Logical volume lv_home successfully resized

[root@localhost ~]# df -h
文件系统              容量  已用  可用 已用%% 挂载点
/dev/mapper/VolGroup-lv_root
50G  2.9G   44G   7% /
tmpfs                 5.9G  100K  5.9G   1% /dev/shm
/dev/sda1             485M   37M  423M   8% /boot
/dev/mapper/VolGroup-lv_home
20G  172M   19G   1% /home

7.查看“Free PE / Size”剩余空间

[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name               VolGroup
System ID
Format                lvm2
Metadata Areas        1
Metadata Sequence No  5
VG Access             read/write
VG Status             resizable
MAX LV                0
Cur LV                3
Open LV               3
Max PV                0
Cur PV                1
Act PV                1
VG Size               1.09 TiB
PE Size               4.00 MiB
Total PE              285022
Alloc PE / Size       19424 / 75.88 GiB
Free  PE / Size       265598 / 1.01 TiB
VG UUID               nSbflh-J7fN-xDvf-zLjL-tFcu-Y5Tm-ybnDk0

8.使用lvextend指令：扩展逻辑卷空间到/dev/mapper/VolGroup-lv_root目录下，也就是“/”目录下。

[root@localhost ~]# lvextend -L +1.01T /dev/mapper/VolGroup-lv_root
Rounding size to boundary between physical extents: 1.01 TiB
Extending logical volume lv_root to 1.06 TiB
Logical volume lv_root successfully resized

9.执行操作，使之生效，中间一定要耐心等待。

[root@localhost ~]# resize2fs -p /dev/mapper/VolGroup-lv_root
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/mapper/VolGroup-lv_root is mounted on /; on-line resizing required
old desc_blocks = 4, new_desc_blocks = 68
Performing an on-line resize of /dev/mapper/VolGroup-lv_root to 284227584 (4k) blocks.
The filesystem on /dev/mapper/VolGroup-lv_root is now 284227584 blocks long.

10.查看分区成功

[root@localhost ~]# df -h
文件系统              容量  已用  可用 已用%% 挂载点
/dev/mapper/VolGroup-lv_root
1.1T  2.9G 1011G   1% /
tmpfs                 5.9G  100K  5.9G   1% /dev/shm
/dev/sda1             485M   37M  423M   8% /boot
/dev/mapper/VolGroup-lv_home
20G  172M   19G   1% /home

11.重启

[root@localhost ~]# shutdown -r now

http://weiruoyu.blog.51cto.com/951650/1119896