Sent: Wednesday, August 05, 2015 at 5:10 PM
From: "Mihai Moldovan" <ionic@ionic.de>
To: "Will Smith" <_will_@mail.com>, x2go-user@lists.x2go.org
Subject: Re: [X2Go-User] Problem connecting to Centos 7 (x2go 4.0.1.19).
On 05.08.2015 03:30 PM, Will Smith wrote:
> Dear All,
>
> I'm having a stange problem when attemping to connect to my Centos server using
> x2goclients (Ubuntu & mac, 4.0.5.0). I'm running firewalld, but port 22 is
> unblocked and I am able to ssh into the machine and forward X traffic. When
> accessing from both a mac and an ubuntu client the session appears to start, but
> then immediately disconnects. The client logs say:
>
> Info: Proxy running in client mode with pid '12054'.
> Session: Starting session at 'Wed Aug 5 12:38:47 2015'.
> Info: Using abstract X11 socket in kernel namespace for accessing DISPLAY=:0.
> Info: Connecting to remote host 'localhost:31003'.
> Info: Connection to remote proxy 'localhost:31003' established.
> Error: The remote NX proxy closed the connection.
> Error: Failure negotiating the session in stage '7'.
> Error: Wrong version or invalid session authentication cookie.
> Session: Terminating session at 'Wed Aug 5 12:38:53 2015'.
> Session: Session terminated at 'Wed Aug 5 12:38:53 2015'.
>
>
> If I attempt to reconnect, I can see the session, but am unable to resume it.
> The strange thing is that if I stop firewalld, I'm able to access the server
> from both clients with no issues, which implies it's a firewall issue, but as I
> say port 22 is unblocked and I can forward X traffic. Is there some other
> obvious firewall setting I've failed do? Any assistance in fixing or diagnosing
> this issue would be highly appreciated.
X2Go makes extensive use of SSH tunnels. I suspect your firewall is too strict
and denies access from localhost to localhost. Please make sure that locally,
all connections are allowed.
Mihai