[Qemu-devel] [Snapshot Mode]

[Benjamin Kormann]

Hi there,

we've been using qemu for quite a while on different platforms and we'd like to perform snapshots on running qemu machines and tar them onto a backup server.
The qemu-img snapshot can only be applied to inactive qemu machines (images), hence this is not applicable. The savevm command within the qemu monitor saves the current cpu state, ram, device state and content of all writable disks. After this command has ended the qemu machine is still running and a backup (copy or tar of file) can potentially be initiated. Since the machine is still up and running changes occur to the qemu image and the final backup file might become corrupted if no snapshot functionality is supported by the underlying filesystem.
Finally my question is:
How can I perform a backup of a system at runtime (at best without the need of any filesystem snapshot)?

Thank you very much in advance.

Cheers,


       - Benny