2019-04-26 KVM虚拟机快照命令行管理

我们使用virsh工具管理kvm, 下面是使用命令行管理快照的案例：
1、查看现有虚拟机, --all参数列出所有虚拟机包括关机的，不加all则列出正在运行的。

root@hs01:~# virsh list --all
 Id    Name                           State
----------------------------------------------------
 ...
 22    axtest99                       running
 -     tacgui                         shut off

2、列出虚拟机axtest99的快照，可以看到有两个快照

root@hs01:~# virsh snapshot-list axtest99
 Name                 Creation Time             State
------------------------------------------------------------
 axtest99-20190426    2019-04-26 12:10:36 +0100 running
 init                 2019-03-30 00:59:33 +0000 shutoff

3、查看虚拟机存储信息

root@hs01:~# virsh domblklist axtest99
Target     Source
------------------------------------------------
hda        /var/lib/libvirt/images/axtest99.qcow2
hdb        -

4、快照只能用在qcow2存储格式，先检查一下

root@hs01:~# virsh dumpxml axtest99 | grep qemu
      <driver name='qemu' type='qcow2'/>
      <driver name='qemu' type='raw'/>

5、创建新快照，可以看到创建成功

root@hs01:~# virsh snapshot-create-as --domain axtest99 --name "test2" --description "This is test"
Domain snapshot test2 created
root@hs01:~# virsh snapshot-list axtest99
 Name                 Creation Time             State
------------------------------------------------------------
 axtest99-20190426    2019-04-26 12:10:36 +0100 running
 init                 2019-03-30 00:59:33 +0000 shutoff
 test2                2019-04-26 14:00:40 +0100 running

6、查看快照信息

root@hs01:~# virsh snapshot-info --domain axtest99 --snapshotname test2
Name:           test2
Domain:         axtest99
Current:        yes
State:          running
Location:       internal
Parent:         axtest99-20190426
Children:       0
Descendants:    0
Metadata:       yes

7、恢复快照，先关机，再恢复

root@hs01:~# virsh shutdown --domain axtest99
Domain axtest99 is being shutdown

root@hs01:~# virsh snapshot-revert --domain axtest99 --snapshotname test2 --running

root@hs01:~# virsh list
 Id    Name                           State
----------------------------------------------------
 ...
 23    axtest99                       running

8、查看虚拟机快照占用磁盘空间,记得我们刚才用“virsh domblklist axtest99” 查看存储？

root@hs01:~# qemu-img info /var/lib/libvirt/images/axtest99.qcow2
image: /var/lib/libvirt/images/axtest99.qcow2
file format: qcow2
virtual size: 40G (42949672960 bytes)
disk size: 12G
cluster_size: 65536
Snapshot list:
ID        TAG                 VM SIZE                DATE       VM CLOCK
1         init                      0 2019-03-30 00:59:33   00:00:00.000
2         axtest99-20190426      2.1G 2019-04-26 12:10:36   38:13:21.690
3         test2                  2.9G 2019-04-26 14:00:40   40:03:16.887
Format specific information:
    compat: 1.1
    lazy refcounts: true
    refcount bits: 16
    corrupt: false
root@hs01:~#

9、删除快照

root@hs01:~# virsh snapshot-delete --domain axtest99 --snapshotname test2
Domain snapshot test2 deleted
root@hs01:~# virsh snapshot-list axtest99
 Name                 Creation Time             State
------------------------------------------------------------
 axtest99-20190426    2019-04-26 12:10:36 +0100 running
 init                 2019-03-30 00:59:33 +0000 shutoff

root@hs01:~# qemu-img info /var/lib/libvirt/images/axtest99.qcow2
image: /var/lib/libvirt/images/axtest99.qcow2
file format: qcow2
virtual size: 40G (42949672960 bytes)
disk size: 12G
cluster_size: 65536
Snapshot list:
ID        TAG                 VM SIZE                DATE       VM CLOCK
1         init                      0 2019-03-30 00:59:33   00:00:00.000
2         axtest99-20190426      2.1G 2019-04-26 12:10:36   38:13:21.690
Format specific information:
    compat: 1.1
    lazy refcounts: true
    refcount bits: 16
    corrupt: false
root@hs01:~#