CentOS下kvm虚拟机磁盘扩展

时间:2016-01-12 21:01 来源:linux.it.net.cn 作者:IT

两种方式:

1.添加一块新的虚拟磁盘

2.扩充原有磁盘的容量大小

注意:

只有磁盘格式为qcow2的磁盘才支持磁盘快照和磁盘动态扩展.

测试的虚拟机磁盘大小和格式.

方法一:添加新磁盘

1.查看已存在盘的大小

[root@kvm-node154 vm]# qemu-img info api1-qcow2.img

image: api1-qcow2.img

file format: qcow2

virtual size: 8.0G (8589934592 bytes)

disk size: 1.5G

cluster_size: 65536

</disk>

2.添加一块qcow2的盘,大小为10G

cd /vm && qemu-img create -f qcow2 api1-qcow2_add1.img 8G

[root@kvm-node154 vm]# qemu-img info api1-qcow2_add1.img

image: api1-qcow2_add1.img

file format: qcow2

virtual size: 10G (10737418240 bytes)

disk size: 140K

cluster_size: 65536

[root@kvm-node154 vm]# ll /vm

总用量 3161404

-rwxr-xr-x 1 qemu qemu 1580662784 1月 11 14:55 api2-qcow2.img

-rw-r--r-- 1 root root 197120 1月 11 14:53 api1-qcow2_add1.img

-rw-r--r-- 1 qemu qemu 1653407744 1月 11 14:55 api1-qcow2.img

3.添加api1-qcow2_add1.img到配置文件中

[root@kvm-node154 vm]# virsh shutdown api1

域 api4 被关闭

[root@kvm-node154 vm]# virsh list --all

Id 名称状态

----------------------------------------------------

2 api2 running

- api1 关闭

virsh edit api1,添加新磁盘

</disk>

4.登录到api1终端,然后查看,并分区/dev/vdb

[root@vm-api1 ~]# fdisk -l

Disk /dev/vdb: 8589 MB, 8589934592 bytes

16 heads, 63 sectors/track, 16644 cylinders

Units = cylinders of 1008 * 512 = 516096 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

5.格式化分区/dev/vdb,并且转换为lvm格式.

fdisk /dev/vdb >> lvm

[root@vm-api1 ~]# fdisk -l

Disk /dev/vdb: 8589 MB, 8589934592 bytes

16 heads, 63 sectors/track, 16644 cylinders

Units = cylinders of 1008 * 512 = 516096 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0xa91642d5

Device Boot Start End Blocks Id System

/dev/vdb1 1 16644 8388544+ 8e Linux LVM

[root@vm-api1 ~]# pvcreate /dev/vdb1

Physical volume "/dev/vdb1" successfully created

[root@vm-api1 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

VolGroup 1 2 0 wz--n- 7.51g 0

[root@vm-api1 ~]# vgextend VolGroup /dev/vdb1

Volume group "VolGroup" successfully extended

[root@vm-api1 ~]# lvs

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

lv_root VolGroup -wi-ao---- 6.71g

lv_swap VolGroup -wi-ao---- 816.00m

[root@vm-api1 ~]# lvextend -l +100%FREE /dev/VolGroup/lv_root

Size of logical volume VolGroup/lv_root changed from 6.71 GiB (1718 extents) to 14.71 GiB (3765 extents).

Logical volume lv_root successfully resized

[root@vm-api1 ~]# resize2fs /dev/VolGroup/lv_root

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/VolGroup/lv_root is mounted on /; on-line resizing required

old desc_blocks = 1, new_desc_blocks = 1

Performing an on-line resize of /dev/VolGroup/lv_root to 3855360 (4k) blocks.

The filesystem on /dev/VolGroup/lv_root is now 3855360 blocks long.

6.再次查看vm的磁盘大小

[root@vm-api1 ~]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root

15G 652M 13G 5% /

tmpfs 246M 0 246M 0% /dev/shm

/dev/vda1 477M 25M 427M 6% /boot

方法二:扩充原有磁盘的大小

1.查看原磁盘的大小

[root@kvm-node154 vm]# qemu-img info /vm/api2-qcow2.img

image: /vm/api2-qcow2.img

file format: qcow2

virtual size: 8.0G (8589934592 bytes)

disk size: 2.4G

cluster_size: 65536

Snapshot list:

ID TAG VM SIZE DATE VM CLOCK

2 api2_ftp 320M 2016-01-08 16:59:52 01:17:18.639

3 api2_httpd 385M 2016-01-08 17:27:16 00:53:48.096

2.关闭vm,然后直接扩充api2-qcow2.img

[root@kvm-node154 vm]# virsh shutdown api2

域 api2 被关闭

[root@kvm-node154 vm]# virsh list --all

Id 名称状态

----------------------------------------------------

3 api1 running

- api2 关闭

[root@kvm-node154 vm]# qemu-img resize api2-qcow2.img +8G

This image format does not support resize //提示不能这种格式不支持扩充

[root@kvm-node154 vm]# virsh

欢迎使用 virsh，虚拟化的交互式终端。

输入：'help' 来获得命令的帮助信息

'quit' 退出

virsh # snapshot-list api2

名称 Creation Time 状态

------------------------------------------------------------

api2_ftp 2016-01-08 16:59:52 +0800 running

api2_httpd 2016-01-08 17:27:16 +0800 running

virsh # snapshot-delete api

api1-qcow2_add1.img api1-qcow2.img api2-qcow2.img

virsh # snapshot-delete api2 api2_ftp

Domain snapshot api2_ftp deleted

virsh # snapshot-delete api2 api2_httpd

Domain snapshot api2_httpd deleted

[root@kvm-node154 vm]# qemu-img resize api2-qcow2.img +8G

Image resized.

3.查看已经扩充的磁盘

[root@kvm-node154 vm]# qemu-img info api2-qcow2.img

image: api2-qcow2.img

file format: qcow2

virtual size: 16G (17179869184 bytes)

disk size: 2.4G

cluster_size: 65536

4.启动vm,然后分区,并格式化

[root@kvm-node154 vm]# virsh start api2

域 api2 已开始

[root@vm-api2 ~]# pvcreate /dev/vda3

Physical volume "/dev/vda3" successfully created

[root@vm-api2 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

VolGroup 1 2 0 wz--n- 7.51g 0

[root@vm-api2 ~]# vgextend VolGroup /dev/vda3

Volume group "VolGroup" successfully extended

[root@vm-api2 ~]# lvextend -l +100%FREE /dev/VolGroup/lv_root

Size of logical volume VolGroup/lv_root changed from 6.71 GiB (1718 extents) to 14.71 GiB (3765 extents).

Logical volume lv_root successfully resized

[root@vm-api2 ~]# resize2fs /dev/VolGroup/lv_root

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/VolGroup/lv_root is mounted on /; on-line resizing required

old desc_blocks = 1, new_desc_blocks = 1

Performing an on-line resize of /dev/VolGroup/lv_root to 3855360 (4k) blocks.

The filesystem on /dev/VolGroup/lv_root is now 3855360 blocks long.

[root@vm-api2 ~]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root

15G 655M 13G 5% /

tmpfs 246M 0 246M 0% /dev/shm

/dev/vda1 477M 25M 427M 6% /boot

成功添加了磁盘.

(责任编辑：IT)