Comment by zsolt-krenak for Hi All! I created a test enviroment with few servers based on CentOS7. When I try to create a snapshot from a running instance it fails. I found this error in log file: 2014-09-10 10:09:37.927 9042 ERROR oslo.messaging.rpc.dispatcher [-] Exception during message handling: unsupported configuration: block copy is not supported with this QEMU binary 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher Traceback (most recent call last): 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo/messaging/rpc/dispatcher.py", line 133, in _dispatch_and_reply 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher incoming.message)) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo/messaging/rpc/dispatcher.py", line 176, in _dispatch 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher return self._do_dispatch(endpoint, method, ctxt, args) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo/messaging/rpc/dispatcher.py", line 122, in _do_dispatch 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher result = getattr(endpoint, method)(ctxt, **new_args) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/exception.py", line 88, in wrapped 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher payload) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/openstack/common/excutils.py", line 68, in __exit__ 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher six.reraise(self.type_, self.value, self.tb) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/exception.py", line 71, in wrapped 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher return f(self, context, *args, **kw) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 274, in decorated_function 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher pass 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/openstack/common/excutils.py", line 68, in __exit__ 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher six.reraise(self.type_, self.value, self.tb) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 260, in decorated_function 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher return function(self, context, *args, **kwargs) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 303, in decorated_function 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher e, sys.exc_info()) 2014-09-10 10:09:37.927 9042 TRACE oslo.messaging.rpc.dispatcher File "/usr/lib ... (more)

Well, as it seems, the live migration wasn't build in the CentOS version of qemu-kvm. We changed the whole system to Ubuntu because we had other CentOS related problmes too.