How to take a Snapshot of a KVM at Location A and Restore that Snapshot at Location B

LinuxRSA · 06-20-2016, 07:00 AM

Hi All

Iv searched snapshots / snapshots KVM on this Forum and Some Posts aren't completed as Resolved

I However require more Info.

I am New to This and would like as much detail as possible.

I have a KVM running at Location A called qa3. - See Below:

Quote:

root@wgcptlogserver:~# hostname
wgcptlogserver
root@wgcptlogserver:~# virsh
Welcome to virsh, the virtualization interactive terminal.

Type: 'help' for help with commands
'quit' to quit

virsh # list
Id Name State
----------------------------------
3 qa3 running

virsh #

Questions:

1 - How do i take a snapshot of qa3 ? What is the Command ?

2 - Where would i find a copy of this snapshot ? Where would it be Stored ?

3 - How do i move this snapshot from Location A to Location B ?

3 - How would i restore it at Location B ? How do i start it up ? What is the Command ?

4 - Is there any Network/Systems Settings that is required when completing such a Task ?

Thanks Guys

ps - This Forum is Flipping AWESOME!!

jefro · 06-21-2016, 02:48 PM

I think this should still be relevant and useful. https://kashyapc.com/2011/10/04/snap...-qcow2-images/

It also may still need a CQOW file to start. Not sure if a raw or other virtual hard drive can support this live.

notKlaatu · 06-21-2016, 03:04 PM

I don't use virt manager much, or any of those frontends, but this might be helpful anyway.

You can create a snapshot file based on a source .qcow2 image with qemu:

Code:

qemu-img create -f qcow2 -b slackware.qcow2 slackware.snap001.img

Then you can run the snapshot file as your new starting point. In other words, the anything you do in that virtual machine only gets preserved in the snapshot file (which itself is a kind of overlay to the original .qcow2 image):

Code:

qemu-kvm [all your usual options here] -drive file=slackware.snap001.img

I have all my qemu notes stored here, if it's of any use: http://straightedgelinux.tk/unix/qemu/?dir=unix

Not entirely sure how it all translates to the virt frontend stuff.

rknichols · 06-21-2016, 06:05 PM

Note that the snapshot is dependent on the original base image. Sending the snapshot to a remote location would be meaningful only if an exact copy of the base image were already there.

dyasny · 06-22-2016, 11:59 AM

You do not need a snapshot in this case. Just stop the VM, use qemu-img convert to clone the disk, and virsh dumpxml to get the VM definitions, copy the disk and the xml to a new location, edit the xml to reflect the new disk name and location, use virsh define to create a new VM based on the copied and modified definition file.