CentOS 调整分区大小

2017年7月14日10:30:50CentOS 调整分区大小已关闭评论 37

 

CentOS调整硬盘分区大小,增加root空间,减少home空间。

CentOS 调整分区大小

1.查看硬盘使用情况。

 

[root@npm ~]# df -h

Filesystem                    Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root    48G   45G    17M  100%  /

tmpfs                         246M     0  246M   0%  /dev/shm

/dev/sda1                     485M   33M  427M   8%  /boot

/dev/mapper/VolGroup-lv_home   50G  180M   47G   1%   /home

 

2.调整home分区大小

 

[root@npm ~]# umount /home

umount /home 如果提示无法卸载,则是有进程占用/home,使用如下命令来终止占用进程:

[root@localhost ~]# fuser -m /home

[root@npm ~]# 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: 11/3303104 files (0.0% non-contiguous), 253351/13207552 blocks

 

注:resize2fs 为重新设定磁盘大小,只是重新指定一下大小,并不对结果有影响,需要下面lvreduce的配合

 

[root@npm ~]# resize2fs -p /dev/mapper/VolGroup-lv_home 2G

resize2fs 1.41.12 (17-May-2010)

Resizing the filesystem on /dev/mapper/VolGroup-lv_home to 524288 (4k) blocks.

Begin pass 2 (max = 32768)

正在重定位块            XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Begin pass 3 (max = 404)

正在扫描inode表          XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

The filesystem on /dev/mapper/VolGroup-lv_home is now 524288 blocks long.

 

挂载上/home,查看磁盘使用情况

 

[root@npm ~]# mount /home

[root@npm ~]# df -h

Filesystem                    Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root   48G   45G   17M 100% /

tmpfs                         246M     0  246M   0% /dev/shm

/dev/sda1                     485M   33M  427M   8% /boot

/dev/mapper/VolGroup-lv_home  2.0G  152M  1.8G   8% /home

 

3.释放空间

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@npm ~]# lvreduce -L 2G /dev/mapper/VolGroup-lv_home

WARNING: Reducing active and open logical volume to 2.00 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 2.00 GiB

Logical volume lv_home successfully resized

 

注:lvreduce -L 20G的意思为设置当前文件系统为20G,如果lvreduce -l 20G是指从当前文件系统上减少20G

使用lvreduce减小逻辑卷的大小。注意:减小后的大小不能小于文件的大小,否则会丢失数据。

可以使用vgdisplay命令等查看一下可以操作的大小。也可以是用fdisk -l命令查看详细信息。

 

[root@npm ~]# df -h

Filesystem                    Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root   48G   45G   16M 100% /

tmpfs                         246M     0  246M   0% /dev/shm

/dev/sda1                     485M   33M  427M   8% /boot

/dev/mapper/VolGroup-lv_home  2.0G  152M  1.8G   8% /home

 

[root@npm ~]# 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               99.51 GiB

PE Size               4.00 MiB

Total PE              25474

Alloc PE / Size       13088 / 51.12 GiB

  Free  PE / Size       12386 / 48.38 GiB

VG UUID               ILLwIo-pQ0o-2Ayw-fYcP-QhcW-A1id-Sozp1f

 

4.增加空余空间到root

 

[root@npm ~]#  lvextend -L +48.38G /dev/mapper/VolGroup-lv_root

Rounding size to boundary between physical extents: 48.38 GiB

Extending logical volume lv_root to 96.54 GiB

Logical volume lv_root successfully resized

[root@npm ~]# 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 = 7

Performing an on-line resize of /dev/mapper/VolGroup-lv_root to 25307136 (4k) blocks.

The filesystem on /dev/mapper/VolGroup-lv_root is now 25307136 blocks long.

 

[root@npm ~]# df -h

Filesystem                    Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root   96G   45G   46G  50%  /

tmpfs                         246M     0  246M   0% /dev/shm

/dev/sda1                     485M   33M  427M   8% /boot

/dev/mapper/VolGroup-lv_home  2.0G  152M  1.8G   8% /home

ITBIJI