Link to home
Start Free TrialLog in
Avatar of Mike Caldwell
Mike CaldwellFlag for United States of America

asked on

Ubuntu VNC server rejects access by client

I have a machine the garage with Ubuntu 14.04.  VNC is running, and remote contact and control are both enabled (check boxes in the GUI).  The icon at the screen top indicates that desktop sharing is enabled.  I try to connect to the remote machine using Tight VNC and Real VNC (preferred) clients from my Windows 10 desktop.  From both I get an error message that they will not connect due to unsupported security requests or settings from the server.  I also tried accessing from another machine here in the office running Ubuntu Mint 17.3 with Remmina.  Remmina says it cannot connect but includes "Protocol security negotiation failure."  So I think I'm close, just need the right security setup.

I am Windows experienced, but little with Linux.  I can deal with installing and running programs, making GUI settings, but if I have to find, open, and edit configuration files, etc, then I need to save your time and mine; that is beyond my skill set.
Avatar of reredok
reredok
Flag of Germany image

Have you test it with port 5800, 5900 in browser or in vnc server itself with ssh
ssh -4 -N -L 5900:localhost:5900 user@host

Open in new window


use TightVNCViewer from a Windows Workstation your.ip.to.vnc:1
Avatar of Mike Caldwell

ASKER

Not sure what to do with your last line.

Previously I was just putting the IP address into Real VNC and TightVNC clients, and got the error messages I reported.  Now by adding the ports I get:

Real VNC (5800)  Just spins, no time out, no connection.
Real VNC (5900)  Same old error message re: security negotiations

TightVNC (5800) GUI goes away, no message, no spinner, just nothing, but I note a second entry in the Windows Processes list.
Tight VNC (5900) Same old error message.  

As for your ssh line: am I to put that into the server machine, or the Ubuntu client?
So at the server (target) machine I ran this, with the results shown:

mikew@MediaMikew:~$ ssh -4 -N -L 5900:localhost:5900 mikew@MediaMikew
The authenticity of host 'mediamikew (127.0.1.1)' can't be established.
ECDSA key fingerprint is 25:d4:80:76:ac:92:3e:db:59:ed:fd:9f:3d:ac:cb:95.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'mediamikew' (ECDSA) to the list of known hosts.
mikew@mediamikews password:
bind: Address already in use
channel_setup_fwd_listener: cannot listen to port: 5900
Could not request local forwarding.
Just tried access with Remmina in the Mint 17.3 machine.  I used the IPaddress:5900 and got an error that it could not connect.  Then tried IPaddress:5800 and got the 'lost in space' response: just waits but does not time out.  I would try it with logging if I knew how to log Remmina.
I was able to install Team Viewer at the server side; I already had the client side on my Windows PC to occasionally help my out of town sister.  It came right up and I now have access.  Not my preferred package, but it works, so I'll leave it at that.  Thanks for the help.
ASKER CERTIFIED SOLUTION
Avatar of reredok
reredok
Flag of Germany image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Thanks for the help.