ubuntu下扩展LVM磁盘的方法分享

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本文介绍下，在ubuntu中扩展LVM磁盘的具体方法，有需要的朋友参考下吧。

当LV空间利用率较大即将耗尽LV空间时，可以将一块新的磁盘或一块磁盘上的/空间加入LV中。

现在/ 空间如下：

复制代码代码示例:

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

查看磁盘状态：

复制代码代码示例:

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

1. 新建LVM类型分区：

复制代码代码示例:

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.

2.创建新的PV

复制代码代码示例:

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]

3. 将PV加入VG组中

复制代码代码示例:

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 ]

4.将VG组中的free空间划出4G到/分区所在的LV

复制代码代码示例:

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

5. 使用resizefs2命令重新加载逻辑卷的大小才能生效

复制代码代码示例:

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.

6.查看增加空间后的/空间

复制代码代码示例:

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

现在发现/ 分区已变大。

以上介绍了，在ubuntu下对即将用尽的LVM磁盘扩容的方法，希望对大家有所帮助。