CentOS7根目录磁盘扩容(/dev/mapper/centos-root 空间不足)

今天在给测试环境搭建k8s系统时，发现master根目录磁盘空间不足，需要扩容，记录如下。

# 查看根分区大小
[root@master ~]# df -h
Filesystem                      Size  Used Avail Use% Mounted on
devtmpfs                         63G     0   63G   0% /dev
tmpfs                            63G     0   63G   0% /dev/shm
tmpfs                            63G  1.3G   62G   2% /run
tmpfs                            63G     0   63G   0% /sys/fs/cgroup
/dev/mapper/cl_geekthings-root   50G   38G   13G  76% /
/dev/sda1                      1014M  311M  704M  31% /boot
/dev/mapper/cl_geekthings-home  918G   12G  906G   2% /home
tmpfs                            13G   12K   13G   1% /run/user/42
tmpfs                            13G     0   13G   0% /run/user/0
overlay                          50G   38G   13G  76% /var/lib/docker/overlay2/70dffe831895bb55d79b4a8f483364a4f736637ccb2f6694f1cf82ba7ff1743d/merged

# 查看磁盘编号
[root@master ~]# ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2

# 这里在vMware vCenter中新增一块硬盘(编辑->新增设备)   再次查看磁盘
[root@master ~]# ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2  /dev/sdb

# 创建pv
[root@master ~]# pvcreate /dev/sdb
  Physical volume "/dev/sdb" successfully created.

# 查看vg组
[root@master ~]# vgs
  VG            #PV #LV #SN Attr   VSize    VFree
  cl_geekthings   1   3   0 wz--n- <999.00g 4.00m

# 扩展vg
[root@master ~]# vgextend cl_geekthings /dev/sdb
  Volume group "cl_geekthings" successfully extended

[root@master ~]# vgs
  VG            #PV #LV #SN Attr   VSize VFree  
  cl_geekthings   2   3   0 wz--n- 1.17t 200.00g

# 扩展lv
[root@master ~]# lvextend -L +200G /dev/mapper/cl_geekthings-root
  Size of logical volume cl_geekthings/root changed from 50.00 GiB (12800 extents) to 250.00 GiB (64000 extents).
  Logical volume cl_geekthings/root successfully resized.

# 系统重新读取大小
[root@master ~]# xfs_growfs /dev/mapper/cl_geekthings-root
meta-data=/dev/mapper/cl_geekthings-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 65536000

# 查看扩容是否成功
[root@master ~]# df -h
Filesystem                      Size  Used Avail Use% Mounted on
devtmpfs                         63G     0   63G   0% /dev
tmpfs                            63G     0   63G   0% /dev/shm
tmpfs                            63G  1.3G   62G   2% /run
tmpfs                            63G     0   63G   0% /sys/fs/cgroup
/dev/mapper/cl_geekthings-root  250G   38G  213G  16% /
/dev/sda1                      1014M  311M  704M  31% /boot
/dev/mapper/cl_geekthings-home  918G   12G  906G   2% /home
tmpfs                            13G   12K   13G   1% /run/user/42
tmpfs                            13G     0   13G   0% /run/user/0
overlay                         250G   38G  213G  16% /var/lib/docker/overlay2/70dffe831895bb55d79b4a8f483364a4f736637ccb2f6694f1cf82ba7ff1743d/merged
[root@master ~]# lsblk
NAME                   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                      8:0    0  1000G  0 disk 
├─sda1                   8:1    0     1G  0 part /boot
└─sda2                   8:2    0   999G  0 part 
  ├─cl_geekthings-root 253:0    0   250G  0 lvm  /
  ├─cl_geekthings-swap 253:1    0  31.5G  0 lvm  
  └─cl_geekthings-home 253:2    0 917.5G  0 lvm  /home
sdb                      8:16   0   200G  0 disk 
└─cl_geekthings-root   253:0    0   250G  0 lvm  /
sr0                     11:0    1   4.1G  0 rom