I want to live migrate a vm from one host to another host. Bu I got this error:

error: internal error: process exited while connecting to monitor: 2015-11-06T07:53:59.006762Z qemu-system-x86_64: Failed to start VNC server on `': Failed to bind socket: Address already in use

The same VNC port is in use at the destination host. Is it possible to change port address without rebooting the server?