Re: [libvirt-users] snapshot of running vm's

No When using external snapshots, the procedure works like this: 1. Create external snapshot => a new file is created ex. 'image.qcow2' 2. Backup the original file ex. 'image.raw' (this file wil not change over time. All writes are done on image.qcow2). 3. Active block commit (commits all writes done on image.qcow2 to image.raw and activate image.raw) 4. delete image.qcow2 If you do a test, you can check which file is in use by 'virsh domblklist $VM' Yes. And it's advisible to also use --quiesce to flush the guests disk cache (the guest agent needs to be installed and running on the guest) And optional use --no-metadata to make shure libvirt isn't following up on these snapshots. This way you can just remove the image.qcow2 with rm Yes, the snapshot is done on a live guest/disk Yes, you have to update the guest xml with 'virsh edit $VM' and enter these lines in the devices section <channel type='unix'> <source mode='bind'> <target type='virtio' name='org.qemu.guest_agent.0'/> </channel> After this, it's possible the qemu guest agent is still not working, edit the xml again and change the port number in the line to a free port (you'll see that for example spice is using the same controller, bus and port...) <address type='virtio-serial' controller='0' bus='0' port='1'/> This way you backup disk state. Most of the times this will be great. For some applications, this isn't sufficient. For instance, a Autodesk Vault Server has a SQL database and a separate file storage. Using Active block commit to backup will not guarantee data concistancy. That's why Autodesk has its own 'best practice'. Here I initiate the Autodesk procedure through a powershell script (I connect to the guest with telnet). You'll need libvirt 1.2.9 or more and Qemu 2.1 (with higher qemu's I have experienced some trouble...)