On 04/26/2016 07:54 AM, Dmitry Mishin wrote:
Hmm. Interesting. But what I'm talking about doesn't involve qemu much. We create an external temporarily delta for images with internal snapshots on libvirt side, then merge it on libvirt side thus, qemu shouldn't be affected at all as far as I understand.
Right now, we are trying the following workaround of this issue: 1) create external snapshot (without metadata) 2) undefine internal snapshots' metadata (because libvirt prohibits migration if detects snapshots) 3) copy metadata & backing file (primary data qcow2 file with internal snapshots) to the destination 4) migrate VM using libvirt 5) define metadata back 6) block-commit - to merge delta to original qcow2 image.
Yes, that looks like a reasonable workaround.
Things would be much simpler, if they were in libvirt rather than in management app on top of it.
It would indeed be easier - but someone has to contribute the patches for it. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org