Ubuntu 14.04 KVM : create snapshots

Reference

https://xdev.me/article/How_to_use_KVM_snapshots

Here are examples of how to take snapshots on KVM.

KVM host : Ubuntu 14.04

VM : Ubuntu 14.04

list snapshots of the VM

virsh # snapshot-list ubuntu1404-vm8 Name                 Creation Time             State ------------------------------------------------------------ virsh #

create a snapshot.

error, KVM does not support taking snapshots with raw format.

I need to convert the VM image format to qcow2 from raw.

virsh # snapshot-create-as ubuntu1404-vm8 ss01 error: unsupported configuration: internal snapshot for disk vda unsupported for storage type raw

shutdown the VM and covert the format type to qcow2.

virsh # shutdown ubuntu1404-vm8 # qemu-img convert -f raw -O qcow2 ubuntu1404-vm8.img ubunt u1404-vm8.qcow2

start the VM

# file ubuntu1404-vm8.qcow2 ubuntu1404-vm8.qcow2: QEMU QCOW Image (unknown version) # mv ubuntu1404-vm8.qcow2 ubuntu1404-vm8.img

edit the XML file of that VM to use qcow2 image.

# virsh edit ubuntu1404-vm8

from

<driver name='qemu' type='raw'/>

to

<driver name='qemu' type='qcow2'/>

start the VM

virsh # start ubuntu1404-vm8 Domain ubuntu1404-vm8 started

create a snapshot.

The VM is paused while creating a snapshot.

virsh # snapshot-create-as ubuntu1404-vm8 ss01 virsh # snapshot-create-as ubuntu1404-vm8 ss02

virsh # snapshot-list ubuntu1404-vm8 Name                 Creation Time             State ------------------------------------------------------------ ss01                 2015-01-04 13:04:13 +0900 running virsh # snapshot-create-as ubuntu1404-vm8 ss02 Domain snapshot ss02 created virsh # virsh # snapshot-list ubuntu1404-vm8 Name                 Creation Time             State ------------------------------------------------------------ ss01                 2015-01-04 13:04:13 +0900 running ss02                 2015-01-04 13:06:13 +0900 running virsh # virsh # snapshot-info --current ubuntu1404-vm8 Name:           ss02 Domain:         ubuntu1404-vm8 Current:        yes State:          running Location:       internal Parent:         ss01 Children:       0 Descendants:    0 Metadata:       yes virsh #

Go to the snapshot “ss01”

virsh # snapshot-revert ubuntu1404-vm8 ss01 virsh #

delete a snapshot.

virsh # snapshot-delete ubuntu1404-vm8 ss02 Domain snapshot ss02 deleted

KVM : how to take snapshots

Here’s an example of how to take snapshots.

# libvirtd --version libvirtd (libvirt) 0.9.8 # qemu-system-x86_64 --version QEMU emulator version 1.0 (qemu-kvm-1.0), Copyright (c) 2003-2008 Fabrice Bellard # uname -ri 3.2.0-31-generic x86_64 # tail -1 /etc/lsb-release DISTRIB_DESCRIPTION="Ubuntu 12.04.1 LTS"

take snapshots of the VM called ubuntu12-04-vm1.

# virsh list --all | grep 10 10 ubuntu12-04-vm1      running

# time virsh snapshot-create ubuntu12-04-vm1

[ while taking snapshots ]

The VM will be suspended while taking the snapshots.

# virsh list --all | grep 10 10 ubuntu12-04-vm1      paused

check the status

# virsh snapshot-list ubuntu12-04-vm1 Name                 Creation Time             State ------------------------------------------------------------ 1349063425           2012-09-29 12:50:25 +0900 running

[ after finishing taking the snapshots ]

In my environment, it took about 13 minutes to take the snapshots.

# time virsh snapshot-create ubuntu12-04-vm1 Domain snapshot 1349063425 created real    13m32.901s user    0m0.052s sys     0m0.016s

# virsh list --all | grep ubuntu12-04-vm1 10 ubuntu12-04-vm1      running

# virsh snapshot-list ubuntu12-04-vm1 Name                 Creation Time             State ------------------------------------------------------------ 1349063425           2012-09-29 12:50:25 +0900 running

[ revert the snapshots ]

# virsh list --all | grep ubuntu12-04-vm1 11 ubuntu12-04-vm1      running # virsh snapshot-list ubuntu12-04-vm1 Name                 Creation Time             State ------------------------------------------------------------ 1349063425           2012-09-29 12:50:25 +0900 running

# time virsh snapshot-revert ubuntu12-04-vm1 1349063425 real    0m5.784s user    0m0.000s sys     0m0.008s

delete the snapshot

# time virsh snapshot-delete ubuntu12-04-vm1 1349063425 Domain snapshot 1349063425 deleted real    0m1.330s user    0m0.008s sys     0m0.000s