怎样调整linux系统分区大小
1、查看当前分区情况
# df -hT 查看目前的分区情况
Filesystem Type Size Used Avail Use% Mounted on
安装centos时，采取了默认的分区方案。从上面可以看出硬盘总100G，lv_root 50G ,lv_home 47G
2、卸载/home
# umount /home/
# df -hT
Filesystem Type Size Used Avail Use% Mounted on
从上面看出home分区已经卸载
3、调整分区大小
# resize2fs -p /dev/mapper/vg_test-lv_home 20G
resize2fs 1.41.12 (17-May-2010)
Please run 'e2fsck -f /dev/mapper/vg_test-lv_home' first.
根据提示执行e2fsck -f /dev/mapper/vg_test-lv_home命令
# resize2fs -p /dev/mapper/vg_test-lv_home 20G 将home分区调整到20G
resize2fs 1.41.12 (17-May-2010)
# mount /home/ 挂载home
# df -hT
Filesystem Type Size Used Avail Use% Mounted on
看到home已经调整到20G
# lvdisplay 查看逻辑卷信息
--- Logical volume ---
# lvreduce -L 20G /dev/mapper/vg_test-lv_home 减少逻辑卷大小到20G
WARNING: Reducing active and open logical volume to 20.00 GiB.
# vgdisplay 查看vg信息
--- Volume group ---
从上面看出有27.57G空闲
把闲置空间扩展到根目录
# lvextend -L +27.57G /dev/mapper/vg_test-lv_root
Rounding size to boundary between physical extents: 27.57 GiB.
Size of logical volume vg_test/lv_root changed from 50.00 GiB (12800 extents) to 77.57 GiB (19858 extents).
Logical volume lv_root successfully resized.
# lvdisplay
--- Logical volume ---
# resize2fs -p /dev/mapper/vg_test-lv_root
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/mapper/vg_test-lv_root is mounted on /; on-line resizing required
old desc_blocks = 4, new_desc_blocks = 5
Performing an on-line resize of /dev/mapper/vg_test-lv_root to 20334592 (4k) blocks.
The filesystem on /dev/mapper/vg_test-lv_root is now 20334592 blocks long.
# df -hT
Filesystem Type Size Used Avail Use% Mounted on
从上面看到根分区大小已经增加。
删除home 逻辑卷并把大小扩展到根目录
注意：一定要备份好/home分区下数据
查看目前的分区挂载情况
# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Thu Aug 4 11:30:04 2016
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/vg_test-lv_root / ext4 defaults 1 1
UUID=adbd2476-a3f6-4fa1-b94c-0ec859e22195 /boot ext4 defaults 1 2
/dev/mapper/vg_test-lv_home /home ext4 defaults 1 2
/dev/mapper/vg_test-lv_swap swap swap defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
# umount /dev/mapper/vg_test-lv_home 卸载home逻辑卷
# lvremove /dev/mapper/vg_test-lv_home 删除逻辑卷
Do you really want to remove active logical volume lv_home? [y/n]: y
Logical volume "lv_home" successfully removed
# lvdisplay
--- Logical volume ---
从上面看出逻辑卷home已经删除
将空闲空间扩展到跟分区
# vgdisplay
--- Volume group ---
从上面看出空闲20G，正好是删除的home逻辑卷大小
# lvextend -L +20G /dev/mapper/vg_test-lv_root
Size of logical volume vg_test/lv_root changed from 77.57 GiB (19858 extents) to 97.57 GiB (24978 extents).
Logical volume lv_root successfully resized.
# lvdisplay
--- Logical volume ---
看到根目录已经扩展
# resize2fs /dev/mapper/vg_test-lv_root
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/mapper/vg_test-lv_root is mounted on /; on-line resizing required
old desc_blocks = 5, new_desc_blocks = 7
Performing an on-line resize of /dev/mapper/vg_test-lv_root to 25577472 (4k) blocks.
The filesystem on /dev/mapper/vg_test-lv_root is now 25577472 blocks long.
# df -hT
Filesystem Type Size Used Avail Use% Mounted on
# cat /etc/fstab
#
如果忘记修改fstab，重启后，根据提示输入密码
# mount / -o remount
然后在修改fstab