On 12/10/2014 11:40 PM, Payes Anand wrote: > Hi, > Is it possible to freeze windows guests for a consistent storage level > snapshot. Yes, if you install qemu-guest-agent in the guest, and wire up your libvirt XML to have the guest-agent channel available. Once you have done that, use the --quiesce flag as part of creating your snapshots. > I was able to freeze Centos guests by issuing the command: > virsh qemu-agent-command <guest_ID> '{"execute":"guest-fsfreeze-freeze"}' That is an unsupported backdoor, because it relies on libvirt-qemu.so. You should really prefer the libvirt commands from libvirt.so instead (the --quiesce flag to 'virsh snapshot-create[-as]'), because it is less likely to get libvirt out of sync by going behind libvirt's back. Also, libvirt 1.2.5 introduced 'virsh domfsfreeze' as the official way to do a guest-agent 'guest'fsfreeze-freeze' command, although since you are using older CentOS builds, your libvirt does not yet have that command supported. > > For CentOS guests, I enabled access between compute nodes and guests > through a socket by setting metadata parameter, hw_qemu_guest_agent=yes for > the guest image. > And then installing qemu-guest-agent inside the guest. > > What steps do i have to follow for windows ? The same steps - qemu-guest-agent is available for both Linux and Windows guests.