3、卷组管理

1、查看已有VG

[root@localhost ~]# vgscan
  Reading all physical volumes.  This may take a while...
  Found volume group "centos" using metadata type lvm2   #系统预设置的卷组
  Found volume group "vg_1" using metadata type lvm2   #用户创建的卷组
[root@localhost ~]# 

2、查看特定VG的详细信息

[root@localhost ~]# vgdisplay vg_1
  --- Volume group ---
  VG Name               vg_1
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  4
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               10.00 GiB
  PE Size               4.00 MiB
  Total PE              2559
  Alloc PE / Size       1024 / 4.00 GiB
  Free  PE / Size       1535 / 6.00 GiB
  VG UUID               RPNJSV-6OpQ-XXVl-FTCe-jrSc-NDXF-SjLZER
   
[root@localhost ~]# 

3、将PV加入已有的VG

[root@localhost ~]# vgextend vg_1 /dev/sdc
  Volume group "vg_1" successfully extended
[root@localhost ~]# 

4、将没有使用的PV从VG中删除

4.1查找VG中没有使用的PV

[root@localhost ~]# pvscan
  PV /dev/sda2   VG centos   lvm2 [19.51 GiB / 40.00 MiB free]
  PV /dev/sdb    VG vg_1     lvm2 [10.00 GiB / 6.00 GiB free]   #总的10G，剩余6G，已使用4G
  PV /dev/sdc    VG vg_1     lvm2 [5.00 GiB / 5.00 GiB free]   #总的5G，剩余5G，未使用
  Total: 3 [34.50 GiB] / in use: 3 [34.50 GiB] / in no VG: 0 [0   ]
[root@localhost ~]# 

4.2将没有使用的PV从VG中删除

[root@localhost ~]# vgreduce vg_1 /dev/sdc
  Removed "/dev/sdc" from volume group "vg_1"
[root@localhost ~]# 

5、删除VG

5.1查看VG是否有分配出LV，如果有则需要先回收LV

[root@localhost ~]# vgdisplay vg_1
  --- Volume group ---
  VG Name               vg_1
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  6
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               10.00 GiB
  PE Size               4.00 MiB
  Total PE              2559
  Alloc PE / Size       1024 / 4.00 GiB   #这里是已经分配出去的资源
  Free  PE / Size       1535 / 6.00 GiB   #这里是未分配的剩余资源
  VG UUID               RPNJSV-6OpQ-XXVl-FTCe-jrSc-NDXF-SjLZER
   
[root@localhost ~]# 

5.2确定要回收的LV

[root@localhost ~]# lvscan
  ACTIVE            '/dev/centos/swap' [2.00 GiB] inherit
  ACTIVE            '/dev/centos/root' [17.47 GiB] inherit
  ACTIVE            '/dev/vg_1/lv_1' [4.00 GiB] inherit  #这个就是在vg_1下的LV
[root@localhost ~]# 

5.3卸载LV并进行回收

[root@localhost ~]# umount /dev/vg_1/lv_1
[root@localhost ~]# lvremove /dev/vg_1/lv_1
Do you really want to remove active logical volume lv_1? [y/n]: y
  Logical volume "lv_1" successfully removed
[root@localhost ~]# 

5.4回收LV之后再次查看VG信息，检查分配出去的LV资源是否已全部回收

[root@localhost ~]# vgdisplay vg_1
  --- Volume group ---
  VG Name               vg_1
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  7
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               10.00 GiB
  PE Size               4.00 MiB
  Total PE              2559
  Alloc PE / Size       0 / 0     #已分配资源为0，当前vg未分配出去资源
  Free  PE / Size       2559 / 10.00 GiB
  VG UUID               RPNJSV-6OpQ-XXVl-FTCe-jrSc-NDXF-SjLZER
   
[root@localhost ~]# 

5.5删除VG

[root@localhost ~]# vgremove vg_1
  Volume group "vg_1" successfully removed
[root@localhost ~]#