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
