管理原已存在的 VG

1. 新增 PV partition
   

   [root@kvm8 ~]# fdisk -uc /dev/vda
   Command (m for help): p
   
   Disk /dev/vda: 1717 MB, 1717987328 bytes
   16 heads, 63 sectors/track, 3328 cylinders, total 3355444 sectors
   Units = sectors of 1 * 512 = 512 bytes
   Sector size (logical/physical): 512 bytes / 512 bytes
   I/O size (minimum/optimal): 512 bytes / 512 bytes
   Disk identifier: 0x0005f7da
   
      Device Boot      Start         End      Blocks   Id  System
   /dev/vda1   *        2048      198655       98304   83  Linux
   /dev/vda2          198656     2656255     1228800   8e  Linux LVM
   /dev/vda3         2656256     2922495      133120   8e  Linux LVM
   
   Command (m for help): n
   Command action
      e   extended
      p   primary partition (1-4)
   e
   Selected partition 4
   First sector (2922496-3355443, default 2922496): 
   Using default value 2922496
   Last sector, +sectors or +size{K,M,G} (2922496-3355443, default 3355443): 
   Using default value 3355443
   
   Command (m for help): p
   
   Disk /dev/vda: 1717 MB, 1717987328 bytes
   16 heads, 63 sectors/track, 3328 cylinders, total 3355444 sectors
   Units = sectors of 1 * 512 = 512 bytes
   Sector size (logical/physical): 512 bytes / 512 bytes
   I/O size (minimum/optimal): 512 bytes / 512 bytes
   Disk identifier: 0x0005f7da
   
      Device Boot      Start         End      Blocks   Id  System
   /dev/vda1   *        2048      198655       98304   83  Linux
   /dev/vda2          198656     2656255     1228800   8e  Linux LVM
   /dev/vda3         2656256     2922495      133120   8e  Linux LVM
   /dev/vda4         2922496     3355443      216474    5  Extended
   
   Command (m for help): n
   First sector (2924544-3355443, default 2924544): 
   Using default value 2924544
   Last sector, +sectors or +size{K,M,G} (2924544-3355443, default 3355443): +20M
   
   Command (m for help): p
   
   Disk /dev/vda: 1717 MB, 1717987328 bytes
   16 heads, 63 sectors/track, 3328 cylinders, total 3355444 sectors
   Units = sectors of 1 * 512 = 512 bytes
   Sector size (logical/physical): 512 bytes / 512 bytes
   I/O size (minimum/optimal): 512 bytes / 512 bytes
   Disk identifier: 0x0005f7da
   
      Device Boot      Start         End      Blocks   Id  System
   /dev/vda1   *        2048      198655       98304   83  Linux
   /dev/vda2          198656     2656255     1228800   8e  Linux LVM
   /dev/vda3         2656256     2922495      133120   8e  Linux LVM
   /dev/vda4         2922496     3355443      216474    5  Extended
   /dev/vda5         2924544     2965503       20480   83  Linux
   
   Command (m for help): t 
   Partition number (1-5): 5
   Hex code (type L to list codes): 8e
   Changed system type of partition 5 to 8e (Linux LVM)
   
   Command (m for help): p
   
   Disk /dev/vda: 1717 MB, 1717987328 bytes
   16 heads, 63 sectors/track, 3328 cylinders, total 3355444 sectors
   Units = sectors of 1 * 512 = 512 bytes
   Sector size (logical/physical): 512 bytes / 512 bytes
   I/O size (minimum/optimal): 512 bytes / 512 bytes
   Disk identifier: 0x0005f7da
   
      Device Boot      Start         End      Blocks   Id  System
   /dev/vda1   *        2048      198655       98304   83  Linux
   /dev/vda2          198656     2656255     1228800   8e  Linux LVM
   /dev/vda3         2656256     2922495      133120   8e  Linux LVM
   /dev/vda4         2922496     3355443      216474    5  Extended
   /dev/vda5         2924544     2965503       20480   8e  Linux LVM
   
   Command (m for help): w
   The partition table has been altered!
   
   Calling ioctl() to re-read partition table.
   
   WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
   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)
   Syncing disks.
   

2. 重新開機
   

   [root@kvm8 ~]# reboot
   

3. 查看 VG vg_kvmusb
   

   [root@kvm8 ~]# vgdisplay vg_kvmusb
     --- Volume group ---
     VG Name               vg_kvmusb
     System ID             
     Format                lvm2
     Metadata Areas        1
     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                1
     Act PV                1
     VG Size               1.17 GiB
     PE Size               4.00 MiB
     Total PE              299
     Alloc PE / Size       287 / 1.12 GiB
     Free  PE / Size       12 / 48.00 MiB  <= 剩 12 個 PE, 48 MiB
     VG UUID               iqDLSv-BhBM-uxdY-sffi-MEb6-NzaM-IVUKVS
   

4. 將分割好的 /dev/vda5 產生 pv
   

   [root@kvm8 ~]# pvcreate /dev/vda5
     Physical volume "/dev/vda5" successfully created
   

5. 將分割好的 /dev/vda5 併入 VG vg_kvmusb
   

   [root@kvm8 ~]# vgextend vg_kvmusb /dev/vda5
     Volume group "vg_kvmusb" successfully extended
   

6. 再觀察 VG vg_kvmusb
   

   [root@kvm8 ~]# vgdisplay vg_kvmusb
     --- Volume group ---
     VG Name               vg_kvmusb
     System ID             
     Format                lvm2
     Metadata Areas        2
     Metadata Sequence No  6
     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               1.18 GiB
     PE Size               4.00 MiB
     Total PE              303
     Alloc PE / Size       287 / 1.12 GiB
     Free  PE / Size       16 / 64.00 MiB  <= 多出 4 個 PE, 16 MiB
     VG UUID               iqDLSv-BhBM-uxdY-sffi-MEb6-NzaM-IVUKVS
   

7. 將 /dev/vda5 移出 VG vg_kvmusb
   

   [root@kvm8 ~]# vgreduce vg_kvmusb /dev/vda5
     Removed "/dev/vda5" from volume group "vg_kvmusb"