centos7 openstack cannot access to instance console

VNC console access failure I installed one vm node openstack for testing, cannot access to new instance console, got error as below, Failed to connect to server (code: 1006) Found some clue from nova log /var/log/nova/nova-consoleauth.log 2018-01-24 01:58:37.323 1331 INFO nova.consoleauth.manager [req-bc9e5095-6306-48ed-821d-28c18634f3d9 2b1047d6cd5644f98de277ba45771651 401c817b58a0446ba78a2c199da8178e – default default] Received Token: 9e97e880-32dc-44ba-a601-efe566aae2fe, …