I want to create online backups of a KVM Windows 10 virtual machine that is managed by libvirt. I have the qemu agent setup in the guest.
If found this wiki entry that suggests the following:
1. create an offline snapshot
$ virsh snapshot-create-as --domain my-vm my-snapshot \
--diskspec vda,file=/export/images/overlay.qcow2 \
--disk-only --atomic --quiesce
2. backup the base image
$ my-backup-tool /path/to/base.image
3. merge fs changes that occured after the snapshot back into the base image
$ virsh blockcommit my-vm hda --active --verbose --pivot
4. remove snapshot
$ virsh snapshot-delete my-vm --metadata my-snapshot
My question: It is suggested by the articcle to provide the --quiesce
parameter to ensure a consistent snapshot creating (i.e. freeze fs activity during creation), but wouldn't one need to do the same for step 3 with the help of e.g. virsh domfsfreeze
? What happens with ongoing fs activity during the blockcommit?