CentOS 安装的时候如果选择了自动分配，那么根目录自会分配 50G，其他的空间会分配给 Home 目录。这就导致我们有些业务无法存储到别的目录，空间会变得很紧张。那么如何划分 home 目录的空间到更目录？
备份 home 目录
因为我这里 home 目录是没有文件的，我们强烈建议在在此类操作过程备份文件。
创建备份文件夹
[root@nginx/]# mkdir /home-backup移动 home 目录下所有文件到备份文件
[root@nginx /]# mv /home/* /home-backup/卸载 /home 目录
[root@nginx ~]# umount /home删除逻辑卷
[root@nginx ~]# lvremove /dev/centos/home
Do you really want to remove active logical volume centos/home? [y/n]: y
Logical volume "home" successfully removed查看卷组可用空间
[root@nginx ~]# vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 7
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 98.80 GiB
PE Size 4.00 MiB
Total PE 25293
Alloc PE / Size 14816 / <57.88 GiB
Free PE / Size 10477 / <40.93 GiB
VG UUID 2efgG6-ImmJ-0Qxe-n9YV-P5Sy-JZGF-wRy3njFree PE / Size 中显示的空间为卷组的空闲空间 40.93 G
3.新建 home 卷
创建新的home卷，并分配空间。由于 home 目录是用户目录，如果删除是会报错的。
L表示大小，默认单位为M；n表示卷名；这里的centos是CentOS7安装系统的时候就默认建立好的卷组名。因为我的 home 没有放什么东西，我们就把刚刚的零头划分给 home 目录算了。
[root@nginx ~]# lvcreate -L 0.93G -n home centos
Rounding up size to full physical extent 956.00 MiB
WARNING: xfs signature detected on /dev/centos/home at offset 0. Wipe it? [y/n]: y
Wiping xfs signature on /dev/centos/home.
Logical volume "home" created.查看逻辑卷home
[root@nginx ~]# lvdisplay再次查看卷组空间大小，可以看到可分配的还有39.99G
[root@nginx ~]# vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 8
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 3
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 98.80 GiB
PE Size 4.00 MiB
Total PE 25293
Alloc PE / Size 15055 / <58.81 GiB
Free PE / Size 10238 / 39.99 GiB
VG UUID 2efgG6-ImmJ-0Qxe-n9YV-P5Sy-JZGF-wRy3nj在新建的逻辑卷home上建立xfs文件系统
[root@nginx ~]# mkfs -t xfs /dev/centos/home
把这个新逻辑卷home挂到之前的文件夹/home中去，直接重启用fstab来挂载也行。
[root@nginx ~]# mount /dev/centos/home /home
再把之前拷出来的东西拷回新的 /home中，不用重启。
[root@nginx ~]# mv /home-backup/* /home/根目录扩容
把剩下的 39.9G现在分配给root卷
[root@nginx ~]# lvextend -L +39.9G /dev/centos/root
Rounding size to boundary between physical extents: 39.90 GiB.
Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to 89.90 GiB (23015 extents).
Logical volume centos/root successfully resized.查看逻辑卷情况
[root@nginx ~]# lvdisplay
--- Logical volume ---
LV Path /dev/centos/swap
LV Name swap
VG Name centos
LV UUID eiPqdo-4FCO-luVJ-K6dx-Sq1D-H9XJ-NLnxcL
LV Write Access read/write
LV Creation host, time oa.juhui-tech.com, 2021-12-21 23:13:02 +0800
LV Status available
# open 2
LV Size <7.88 GiB
Current LE 2016
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:1
--- Logical volume ---
LV Path /dev/centos/root
LV Name root
VG Name centos
LV UUID jbc0hA-HzX0-nbmQ-pRRU-rQl6-NV96-k53SgL
LV Write Access read/write
LV Creation host, time oa.juhui-tech.com, 2021-12-21 23:13:03 +0800
LV Status available
# open 1
LV Size 89.90 GiB
Current LE 23015
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
--- Logical volume ---
LV Path /dev/centos/home
LV Name home
VG Name centos
LV UUID DLcx0h-Hvgq-nUyy-6IUQ-LQKw-4JAq-5QzLAe
LV Write Access read/write
LV Creation host, time nginx, 2022-11-25 00:08:04 +0800
LV Status available
# open 1
LV Size 956.00 MiB
Current LE 239
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:2扩容 root 目录
[root@nginx ~]# xfs_growfs /dev/centos/root
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=3276800 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=13107200, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=6400, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 13107200 to 23567360最好查看扩容后的情况
如果后续还需要扩容的话，可以参考 Centos 根目录空间扩容 。