ubuntu下扩展LVM磁盘的方法分享

root@ubuntu :~# df -h
文件系统            容量  已用 可用 已用% 挂载点
/dev/mapper/ubuntu-root
                      4.5G  792M  3.5G  19% /
none                  244M  224K  243M   1% /dev
none                  249M  4.0K  249M   1% /dev/shm
none                  249M   36K  249M   1% /var/run
none                  249M     0  249M   0% /var/lock
none                  249M     0  249M   0% /lib/init/rw
/dev/sda1             228M   19M  198M   9% /boot

root@ubuntu :~# fdisk -l
Disk /dev/sda: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0000d2ec

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          32      248832   83  linux
Partition 1 does not end on cylinder boundary.
/dev/sda2              32         653     4990977    5  Extended
Partition 2 does not end on cylinder boundary.
/dev/sda5              32         653     4990976   8e  Linux LVM

Disk /dev/sdb: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/sdb doesn't contain a valid partition table

root@ubuntu :~# fdisk /dev/sdb  对硬盘sdb进行分区

Command (m for help): n  创建新的分区
Command action
   e   extended
   p   primary partition (1-4)
   p                 创建主分区
Partition number (1-4): 1  
First cylinder (1-522, default 1):  默认值
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-522, default 522):  默认值
Using default value 522

Command (m for help): p        //查看当前分区

Disk /dev/sdb: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x542e4b15

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         522     4192933+  83  Linux

Command (m for help): t  改变分区类型
Selected partition 1
Hex code (type L to list codes): 8e  更改为LVM类型分区
Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): w   保持退出
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

root@ubuntu :~# partprobe  使用partprobe指令更新内核的中硬盘分区表
root@ubuntu :~# pvcreate /dev/sdb1  创建新的PV
  Physical volume "/dev/sdb1" successfully created

root@ubuntu :~# pvscan    新创建的PV但是尚未加入任何VG组
  PV /dev/sda5   VG ubuntu          lvm2 [4.76 GiB / 12.00 MiB free]
  PV /dev/sdb1                      lvm2 [4.00 GiB]
  Total: 2 [8.76 GiB] / in use: 1 [4.76 GiB] / in no VG: 1 [4.00 GiB]

root@ubuntu :~# vgdisplay   //查看VG组的详细信息
  --- Volume group ---
  VG Name               ubuntu
  System ID            
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  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               4.76 GiB
  PE Size               4.00 MiB
  Total PE              1218
  Alloc PE / Size       1215 / 4.75 GiB
  Free  PE / Size       3 / 12.00 MiB
  VG UUID               jeRoTV-fYcT-e5qf-N2rk-m6Ky-eH1W-NSRm1s
  
root@ubuntu :~# vgextend ubuntu /dev/sdb1  //添加磁盘到VG组
  Volume group "ubuntu" successfully extended

root@ubuntu :~# pvscan  // /dev/sdb1加入到ubuntu组中
  PV /dev/sda5   VG ubuntu   lvm2 [4.76 GiB / 12.00 MiB free]
  PV /dev/sdb1   VG ubuntu   lvm2 [4.00 GiB / 4.00 GiB free]
  Total: 2 [8.75 GiB] / in use: 2 [8.75 GiB] / in no VG: 0 [0   ]

root@ubuntu :~# lvdisplay  //查看LV Name
  --- Logical volume ---
  LV Name                /dev/ubuntu/root
  VG Name                ubuntu
  LV UUID                ig0Es7-8tMQ-Uyiq-szHY-V8b0-pnC1-1lFyKn
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                4.49 GiB
  Current LE             1149

root@ubuntu :~# lvextend -L +4G  /dev/ubuntu/root // 将VG组中的free空间4G加到/分区所在的LV
  Extending logical volume root to 8.49 GiB
  Logical volume root successfully resized

root@ubuntu :~# resize2fs /dev/ubuntu/root
resize2fs 1.41.11 (14-Mar-2010)
Filesystem at /dev/ubuntu/root is mounted on /; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 1
Performing an on-line resize of /dev/ubuntu/root to 2225152 (4k) blocks.
The filesystem on /dev/ubuntu/root is now 2225152 blocks long.

root@ubuntu :~# df -h
文件系统            容量  已用 可用 已用% 挂载点
/dev/mapper/ubuntu-root
                      8.4G  793M  7.2G  10% /
none                  244M  228K  243M   1% /dev
none                  249M  4.0K  249M   1% /dev/shm
none                  249M   36K  249M   1% /var/run
none                  249M     0  249M   0% /var/lock
none                  249M     0  249M   0% /lib/init/rw
/dev/sda1             228M   19M  198M   9% /boot