When I try using vncviewer to remote access a libvirt virtual machine, it shows error:

VNC Viewer Free Edition 4.1.1 for X - built Apr  2 2015 21:51:06
Copyright (C) 2002-2005 RealVNC Ltd.
See http://www.realvnc.com for information on VNC.

Wed Dec 16 11:24:12 2015
 main:        unable to connect to host: Connection refused (111)



Add listen command to libvirt xml configration file.

1) XML configuration saved in /etc/libvirtd/qemu or you could edit it by "virsh edit node1"

2) add "listen='0:0:0:0'"


<graphics type='vnc' port='-1' autoport='yes'/>

change to 

<graphics type='vnc' port='-1' autoport='yes' listen=''/>

or using passwd

<graphics type='vnc' port='-1' autoport='yes' listen='' passwd='****'/>

Then everything works fine.