Hi. I'm wondering if it is possible at all to do a consistent backup of a running kvm guest without shutting it down:
If I use the snapshot mode, I'll get a snapshot of the disk which is consistent, e.g. it is in the state of the disk at the time the snapshot was done. But I loose all the system state. So when I boot up the snapshot the filesystem could be inconsistent and maybe there is some data missing that was in ram only when the snapshot has been taken (databases) -> so this is no option if someone is really concerned about the integrity of his data.
When using the suspend mode, the hypervisor pauses the machine while doing the backup. The disk is consistent, but the data isn't necessarily. It's the same case as above.
So I think the only option to do a consistent backup without stopping the machine is to save a KVM-Snapshot (with system state and disk).
Is there a way to do this? Any opinions on this?
If I use the snapshot mode, I'll get a snapshot of the disk which is consistent, e.g. it is in the state of the disk at the time the snapshot was done. But I loose all the system state. So when I boot up the snapshot the filesystem could be inconsistent and maybe there is some data missing that was in ram only when the snapshot has been taken (databases) -> so this is no option if someone is really concerned about the integrity of his data.
When using the suspend mode, the hypervisor pauses the machine while doing the backup. The disk is consistent, but the data isn't necessarily. It's the same case as above.
So I think the only option to do a consistent backup without stopping the machine is to save a KVM-Snapshot (with system state and disk).
Is there a way to do this? Any opinions on this?
