Hi Everybody, Since qemu v1.1.0 upstream commit 8cf364, qemu implemented shared-flag handling the default qemu vnc server behavior from mode 'ignore' to 'allow-exclusive'. The direct effect is as follows for libvirt user: vncviwer client: before: all client could share desktop without any option after: all client need -Shared options for desktop sharing. One client without -Shared option breaks others's connection virt-viewer: before: virt-viewer could support multiple desktop sharing after: only one active connection If we need to keep the original vnc behavior at libvirt level, the '-vnc :1,share=ignore' need to add into qemu commandline. Any ideas about this? Reference RFB Protocol about shared-flag Shared-flag is non-zero (true) if the server should try to share the desktop by leaving other clients connected, zero (false) if it should give exclusive access to this client by disconnecting all other clients From qemu doc: Set display sharing policy. 'allow-exclusive' allows clients to ask for exclusive access. As suggested by the rfb spec this is implemented by dropping other connections. Connecting multiple clients in parallel requires all clients asking for a shared session (vncviewer: -shared switch). This is the default. 'force-shared' disables exclusive client access. Useful for shared desktop sessions, where you don't want someone forgetting specify -shared disconnect everybody else. 'ignore' completely ignores the shared flag and allows everybody connect unconditionally. Doesn't conform to the rfb spec but is traditional qemu behavior. Guannan