Dear all,
trying to solved troubles with VNC, restarted opennebula-novnc service.
It’s not possible to restart it any longer, because:
systemctl start opennebula-novnc.service
A dependency job for opennebula-sunstone.service failed. See “systemctl status opennebula-novnc.service” and “journalctl -xe” for details.
"
OpenNebula 4.12.3
Hello, you should look at status systemctl status opennebula-novnc.service -l and you will see… also check logs in /var/log/oned/
Dear Kristian,
thank you for your reply.
log does not look really comprehensive:
● opennebula-novnc.service - OpenNebula noVNC Server
Loaded: loaded (/lib/systemd/system/opennebula-novnc.service; disabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Mo 2017-12-11 18:08:46 CET; 19h ago
Process: 24439 ExecStart=/usr/bin/novnc-server start (code=exited, status=1/FAILURE)
Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/lib/ruby/2.3.0/logger.rb:695:in set_dev' Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/lib/ruby/2.3.0/logger.rb:635:ininitializ
Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/lib/ruby/2.3.0/logger.rb:353:in new' Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/lib/ruby/2.3.0/logger.rb:353:ininitializ
Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/bin/novnc-server:53:in new' Dez 11 18:08:46 f1 novnc-server[24439]: from /usr/bin/novnc-server:53:in'
Dez 11 18:08:46 f1 systemd[1]: opennebula-novnc.service: Control process exited, code=exited status=
Dez 11 18:08:46 f1 systemd[1]: Failed to start OpenNebula noVNC Server.
Dez 11 18:08:46 f1 systemd[1]: opennebula-novnc.service: Unit entered failed state.
Dez 11 18:08:46 f1 systemd[1]: opennebula-novnc.service: Failed with result ‘exit-code’.
~
and what is in /var/log/one/novnc.log
Dear Kristian,
thank you for your reply.
Accessing a log gives us:
127.0.0.1 - - [11/Dec/2017 16:23:25] 127.0.0.1: Plain non-SSL (ws://) WebSocket connection
127.0.0.1 - - [11/Dec/2017 16:23:25] 127.0.0.1: Version hybi-13, base64: 'False’
127.0.0.1 - - [11/Dec/2017 16:23:25] 127.0.0.1: Path: '/?token=g3klvibppzjbd7uwpfwc’
127.0.0.1 - - [11/Dec/2017 16:23:25] connecting to: 10.10.0.17:6126
127.0.0.1 - - [11/Dec/2017 16:25:47] 127.0.0.1: Plain non-SSL (ws://) WebSocket connection
127.0.0.1 - - [11/Dec/2017 16:25:47] 127.0.0.1: Version hybi-13, base64: 'False’
127.0.0.1 - - [11/Dec/2017 16:25:47] 127.0.0.1: Path: '/?token=kkb8v93p9rux96e4r4za’
127.0.0.1 - - [11/Dec/2017 16:25:47] connecting to: 10.10.0.17:6128
127.0.0.1 - - [11/Dec/2017 16:27:52] 127.0.0.1: Plain non-SSL (ws://) WebSocket connection
127.0.0.1 - - [11/Dec/2017 16:27:52] 127.0.0.1: Version hybi-13, base64: ‘False’
127.0.0.1 - - [11/Dec/2017 16:27:52] 127.0.0.1: Path: ‘/?token=r0jboux494wfr229352n’
127.0.0.1 - - [11/Dec/2017 16:27:52] connecting to: 10.10.0.17:6128
127.0.0.1 - - [11/Dec/2017 16:28:17] code 400, message Bad request syntax (’\x88\x8f\x10i\xb9\xba\x13\x81\xed\xdbb\x0e\xdc\xce0’)
127.0.0.1 - - [11/Dec/2017 16:39:06] 127.0.0.1: Plain non-SSL (ws://) WebSocket connection
127.0.0.1 - - [11/Dec/2017 16:39:06] 127.0.0.1: Version hybi-13, base64: 'False’
127.0.0.1 - - [11/Dec/2017 16:39:06] 127.0.0.1: Path: '/?token=h9ia8llpso3q30jlbxrg’
127.0.0.1 - - [11/Dec/2017 16:39:06] connecting to: 10.10.0.13:6131
127.0.0.1 - - [11/Dec/2017 16:55:46] 127.0.0.1: Plain non-SSL (ws://) WebSocket connection
127.0.0.1 - - [11/Dec/2017 16:55:46] 127.0.0.1: Version hybi-13, base64: 'False’
127.0.0.1 - - [11/Dec/2017 16:55:46] 127.0.0.1: Path: '/?token=wb1y2xp4nmfhiez6zbmq’
127.0.0.1 - - [11/Dec/2017 16:55:46] connecting to: 10.10.0.13:6131
where 10.10.0.13 is the current host with frontend installed.
hmm, did you installed all ruby gems?
I think so. Because noVNC was working from time to time, but showing the connection time out too often. So I decided to restart the sunstone service with service opennebula-sunstone stop and can’t start it any longer.
hmm, I dont know, I can suggest you to upgrade to latest opennebula 
version 4 is pretty old
Try sudo gem install xmlrpc
Regards
Kevin M.