I snapshot my guests live with qemu-guest-agent. It works pretty much flawlessly with qcow2, but even with raw I can almost always boot off of a snapshot. I combine this with zfs and hourly snapshots and replication and have a really usable backup and DR system that works with my guests, both Windows and Linux. You should test it with qemu-guest-agent and then try to boot off of it and see if you run into issues. I've been doing this for 2+ years. On 10/15/2018 3:29 PM, Lentes, Bernd wrote:
Hi,
i have a two node cluster with virtual guests as resources. I'd like to snapshot the guests once in the night and thought i had a procedure. But i realize that things in a cluster are a bit more complicated than expected :-))
I will shutdown the guests to have a clean snapshot. I can shutdown the guests via pacemaker. But then arises the first problem:
When i issue a "virsh snapshot-create-as" libvirt needs the domain name as a parameter. but libvirt does not know the domains any longer. When the guests are shutdown a "virsh list --all" on both nodes does not show any domain.
A look in the respective resource agent VirtualDomain explains why: The domain is started with virsh create:
"# The 'create' command guarantees that the domain will be # undefined on shutdown, ...
OK: Now i could of course define all domains with a virsh define.
But then i have immediately the next problem. Now i'd create the snapshots with "virsh snapshot-create-as" and starts the domains afterwards via cluster. But let's assume i issue that on node 1 and some guests are started afterwards via pacemaker on node 2. I can't predict on which node the guests are starting.
Then i don't get a snapshot, right ?
What to do ?
Bernd
-- Doug Hughes Keystone NAP Fairless Hills, PA 1.844.KEYBLOCK (439.2562)