如何修改CentOS分区大小？

Linux Linux运维 2016年9月6日

当我们发现CentOS硬盘容量分配不合理时或者分区不够用时，就需要调整磁盘分区容量的大小。在工作中就出现了代码传不上去的问题，刚开始以为网络不好，后面经过排查发现所在磁盘满了。下面雷雪松就详细的讲解下如何修改CentOS分区大小以及CentOS分区常用的操作。

1、把空闲分区4.7G分给/dev/mapper/system-home
[cc lang=”bash” escaped=”true”][root@Linux ~]# lvextend -L +4.7G /dev/mapper/system-usr
Rounding size to boundary between physical extents: 4.70 GiB
Extending logical volume usr to 21.70 GiB
Logical volume usr successfully resized
[root@hbdsftest ~]# resize2fs -p /dev/mapper/system-usr
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/mapper/system-usr is mounted on /usr; on-line resizing required
old desc_blocks = 2, new_desc_blocks = 2
Performing an on-line resize of /dev/mapper/system-usr to 5689344 (4k) blocks.
The filesystem on /dev/mapper/system-usr is now 5689344 blocks long.[/cc]

2、查看空闲分区
[cc lang=”php” escaped=”true”][root@Linux ~]# vgdisplay
— Volume group —
VG Name system
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 14
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 6
Open LV 6
Max PV 0
Cur PV 1
Act PV 1
VG Size 91.73 GiB
PE Size 16.00 MiB
Total PE 5871
Alloc PE / Size 5869 / 91.70 GiB
Free PE / Size 2 / 32.00 MiB
VG UUID E4AhCO-kIEN-mWEx-q6CR-fAuw-vfzO-5qWO2r[/cc]

3、原有分区/dev/mapper/system-opt减少5G
[cc lang=”php” escaped=”true”][root@hbdsftest ~]# umount /opt/
[root@hbdsftest ~]# e2fsck -f /dev/mapper/system-opt #强制检查文件系统/dev/mapper/system-opt是否有错误迹象
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/system-opt: 14/655360 files (0.0% non-contiguous), 79709/2621440 blo cks
[root@hbdsftest ~]# resize2fs -p /dev/mapper/system-opt 5G #调整/dev/mapper/system-opt为5G
resize2fs 1.41.12 (17-May-2010)
正在重定位块 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXblocks.
Begin pass 3 (max = 80)
正在扫描inode表 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Begin pass 4 (max = 6)
正在更新inode引用 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
The filesystem on /dev/mapper/system-opt is now 1310720 blocks long.
[root@hbdsftest ~]# mount /opt/[/cc]

4、设置空闲分区
[cc lang=”php” escaped=”true”][root@hbdsftest ~]# lvreduce -L 5G /dev/mapper/system-opt
WARNING: Reducing active and open logical volume to 5.00 GiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce opt? [y/n]: y
Reducing logical volume opt to 5.00 GiB
Logical volume opt successfully resized[/cc]
注：lvreduce -L 5G的意思为设置当前文件系统为5G，如果lvreduce -l 5G是指从当前文件系统上减少5G

5、使用df命令查看磁盘空间大小、使用情况、可用空间、使用率以及挂载点
[cc lang=”php” escaped=”true”][root@Linux ~]# df -h[/cc]

6、扩展system卷组
[cc lang=”php” escaped=”true”][root@hbdsftest ~]# vgextend system /dev/sdb
No physical volume label read from /dev/sdb
Physical volume /dev/sdb not found
Physical volume “/dev/sdb” successfully created
Volume group “system” successfully extended[/cc]

来源：如何修改CentOS分区大小？