Hi, If I make an external snapshot using the method of active block commit, I get these messages after the block commit: $virsh snapshot-create-as CmsrvAPP2 --name onderhoudscript --disk-only --atomic --quiesce --no-metadata Domein snapshot onderhoudscript is aangemaakt $virsh blockcommit CmsrvAPP2 vda --verbose --pivot 2016-01-03 18:14:52.784+0000: 15861: info : libvirt version: 1.2.16, package: 1.2.16-2ubuntu11.15.10.1 2016-01-03 18:14:52.784+0000: 15861: warning : virEventPollUpdateTimeout:268 : Ignoring invalid update timer -1 Successfully pivoted I've googled the 'invalid update timer -1' warning and found some messages about losing disk data after snapshot commits (using an other methode of snapshotting). I've done some tests with snapshotting, creating a file in the guest, doing the blockcommit. And I don't notice something weird. The only weird thing is: it only happens with one of the ten guests that run on the host... Should I worry about this? Greetings and thanks in advance, Dominique.