Comment 0 for bug 1715254

Users reported they were unable to connect to instance consoles via either Horizon or direct URL. Upon investigation we found errors suggesting the address and port were in use:

2017-08-23 14:51:56.248 1355081 INFO nova.console.websocketproxy [-] WebSocket server settings:
2017-08-23 14:51:56.248 1355081 INFO nova.console.websocketproxy [-] - Listen on 0.0.0.0:6080
2017-08-23 14:51:56.248 1355081 INFO nova.console.websocketproxy [-] - Flash security policy server
2017-08-23 14:51:56.248 1355081 INFO nova.console.websocketproxy [-] - Web server (no directory listings). Web root: /usr/share/novnc
2017-08-23 14:51:56.248 1355081 INFO nova.console.websocketproxy [-] - No SSL/TLS support (no cert file)
2017-08-23 14:51:56.249 1355081 CRITICAL nova [-] error: [Errno 98] Address already in use
2017-08-23 14:51:56.249 1355081 ERROR nova Traceback (most recent call last):
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/bin/nova-novncproxy", line 10, in <module>
2017-08-23 14:51:56.249 1355081 ERROR nova sys.exit(main())
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/lib/python2.7/dist-packages/nova/cmd/novncproxy.py", line 41, in main
2017-08-23 14:51:56.249 1355081 ERROR nova port=CONF.vnc.novncproxy_port)
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/lib/python2.7/dist-packages/nova/cmd/baseproxy.py", line 73, in proxy
2017-08-23 14:51:56.249 1355081 ERROR nova RequestHandlerClass=websocketproxy.NovaProxyRequestHandler
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/lib/python2.7/dist-packages/websockify/websocket.py", line 909, in start_server
2017-08-23 14:51:56.249 1355081 ERROR nova tcp_keepintvl=self.tcp_keepintvl)
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/lib/python2.7/dist-packages/websockify/websocket.py", line 698, in socket
2017-08-23 14:51:56.249 1355081 ERROR nova sock.bind(addrs[0][4])
2017-08-23 14:51:56.249 1355081 ERROR nova File "/usr/lib/python2.7/socket.py", line 224, in meth
2017-08-23 14:51:56.249 1355081 ERROR nova return getattr(self._sock,name)(*args)
2017-08-23 14:51:56.249 1355081 ERROR nova error: [Errno 98] Address already in use
2017-08-23 14:51:56.249 1355081 ERROR nova

This lead us to the discovery of a stuck nova-novncproxy process after stopping the service. Once we sent a kill -HUP to that process, we were able to start the nova-novncproxy and restore service to the users.

This was not the first time we have had to restart nova-novncproxy services after users reported that were unable to connect with VNC. This time, as well as at least 2 other times, we have seen the following errors in the nova-novncproxy.log during the time frame of the issue:

gaierror: [Errno -8] Servname not supported for ai_socktype

which seems to correspond to a log entries for connection strings with an invalid port ('port': u'-1'). As well as a bunch of:

error: [Errno 104] Connection reset by peer