Centos7扩容根目录

1、原磁盘大小

2、扩容后磁盘

3、使用sudo fdisk -l是否增加40G磁盘

4、使用 sudo fidsk /dev/sda对新增40G空间进行分区

[root@docker ~]# sudo fdisk /dev/sda

欢迎使用 fdisk (util-linux 2.23.2)。

更改将停留在内存中，直到您决定将更改写入磁盘。
使用写入命令前请三思。


命令(输入 m 获取帮助)：n
Partition type:
   p   primary (3 primary, 0 extended, 1 free)
   e   extended
Select (default e): p
已选择分区 4
起始 扇区 (125829120-209715199，默认为 125829120)：
将使用默认值 125829120
Last 扇区, +扇区 or +size{K,M,G} (125829120-209715199，默认为 209715199)：
将使用默认值 209715199
分区 4 已设置为 Linux 类型，大小设为 40 GiB

命令(输入 m 获取帮助)：w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: 设备或资源忙.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
正在同步磁盘。

5、查看卷分组，得知卷组名为"centos"

[root@docker ~]# sudo vgdisplay -v

 --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  5
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               58.99 GiB
  PE Size               4.00 MiB
  Total PE              15102
  Alloc PE / Size       15101 / <58.99 GiB
  Free  PE / Size       1 / 4.00 MiB
  VG UUID               P53Hyg-c8eU-ULyp-syrG-iCoe-eovF-fgLLk2
   
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                1kehce-AXda-dX2C-pjoV-sJfK-fUyf-Imr7uh
  LV Write Access        read/write
  LV Creation host, time localhost.localdomain, 2020-06-17 15:57:01 +0800
  LV Status              available
  # open                 2
  LV Size                2.00 GiB
  Current LE             512
  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                cOQdeQ-ULkv-7gaF-jVUt-C3O5-c4ur-70PIZp
  LV Write Access        read/write
  LV Creation host, time localhost.localdomain, 2020-06-17 15:57:01 +0800
  LV Status              available
  # open                 1
  LV Size                <56.99 GiB
  Current LE             14589
  Segments               2
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0
   
  --- Physical volumes ---
  PV Name               /dev/sda2     
  PV UUID               a22Uci-fiA3-bmrN-SpL0-5IAS-cUGu-bs1ae9
  PV Status             allocatable
  Total PE / Free PE    9983 / 0
   
  PV Name               /dev/sda3     
  PV UUID               OOc3lc-IyGu-xkvm-S3hm-OVgO-vFfk-2HfYc2
  PV Status             allocatable
  Total PE / Free PE    5119 / 1

6、为新增分区创建物理卷,如出现未发现设备，需要重启系统

[root@docker ~]# sudo pvcreate /dev/sda4
 Physical volume "/dev/sda4" successfully created

7、扩容/dev/sda4分区到centos卷组

[root@docker ~]# sudo vgextend centos /dev/sda4
 Volume group "centos" successfully extended

8、查看根目录路径，并扩容到根目录

#查看挂载
[root@docker ~]# sudo df -h

#扩容到根目录，虽然磁盘扩容40G，但是磁盘可使用不足40G，所以扩容时写入的是39.99G,如写40G会导致扩容失败
[root@docker ~]# sudo lvextend -L +39.99G /dev/mapper/centos-root
  Rounding size to boundary between physical extents: 39.99 GiB.
  Size of logical volume centos/root changed from <56.99 GiB (14589 extents) to 96.98 GiB (24827 extents).
  Logical volume centos/root successfully resized

9、执行xfs_growfs /dev/mapper/centos-root

[root@docker ~]# sudo xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=512    agcount=7, agsize=2424576 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=14939136, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=4735, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 14939136 to 25422848

10、查看

[root@docker ~]# sudo df -h