# centos8使用lvextend对根目录进行扩容

> 记录一次完成的扩容操作

``` linux

[root@localhost data]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/cl-root 50G 7.0G 44G 14% /

/dev/mapper/cl-home 2.7T 19G 2.7T 1% /home

# 当前服务器根目录只有50G, /home目录却有2.7T, 需要进行逻辑卷调整

```

``` linux

# 卸载home节点, 这一步可能会遇到磁盘繁忙的情况, 需要解除占用, 不行的话，可以试试重启

[root@localhost data]# umount /home

```

``` linux

[root@localhost data]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/cl-root 50G 7.0G 44G 14% /

# 可以看到 /home节点已经被卸载(注意备份数据, home数据会被清理)

```

``` linux

# 删除逻辑分区

[root@localhost data]# lvremove /dev/mapper/cl-home

Do you really want to remove active logical volume cl/home? [y/n]: y

Logical volume "home" successfully removed

```

``` linux

# 扩展根节点大小

[root@localhost data]# lvextend -L +2200G /dev/mapper/cl-root

Size of logical volume cl/root changed from 50.00 GiB (12800 extents) to <2.20 TiB (576000 extents).

Logical volume cl/root successfully resized.

[root@localhost data]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/cl-root 50G 7.0G 44G 14% /

# 此时发现改动还未生效

```

``` linux

# 使逻辑分区调整生效, centos7的命令好像不太一样

[root@localhost data]# xfs_growfs /

meta-data=/dev/mapper/cl-root isize=512 agcount=4, agsize=3276800 blks

= sectsz=4096 attr=2, projid32bit=1

= crc=1 finobt=1, sparse=1, rmapbt=0

= reflink=1

data = bsize=4096 blocks=13107200, imaxpct=25

= sunit=0 swidth=0 blks

naming =version 2 bsize=4096 ascii-ci=0, ftype=1

log =internal log bsize=4096 blocks=6400, version=2

= sectsz=4096 sunit=1 blks, lazy-count=1

realtime =none extsz=4096 blocks=0, rtextents=0

data blocks changed from 13107200 to 589824000

[root@localhost data]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/cl-root 2.2T 23G 2.2T 1% /

# 此时发现扩容已经生效了

```

``` linux

# 重建home分区

[root@localhost data]# lvcreate -L 400G -n home cl

Logical volume "home" created.

[root@localhost data]# mkfs.xfs /dev/mapper/cl-home

meta-data=/dev/mapper/cl-home isize=512 agcount=4, agsize=26214400 blks

= sectsz=4096 attr=2, projid32bit=1

= crc=1 finobt=1, sparse=1, rmapbt=0

= reflink=1

data = bsize=4096 blocks=104857600, imaxpct=25

= sunit=0 swidth=0 blks

naming =version 2 bsize=4096 ascii-ci=0, ftype=1

log =internal log bsize=4096 blocks=51200, version=2

= sectsz=4096 sunit=1 blks, lazy-count=1

realtime =none extsz=4096 blocks=0, rtextents=0

# 挂载/home节点

[root@localhost data]# mount /dev/mapper/cl-home /home

[root@localhost data]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/cl-root 2.2T 23G 2.2T 1% /

/dev/mapper/cl-home 400G 2.9G 397G 1% /home

```

## 参考文章

jianshu.com/p/4c7acf819046