Hey Roland,

I'm sorry but I'm quite busy right now. 
Following things to try:

Kill all sessions on your server.
Use the root command to list all users sessions with:
sudo x2golistsessions_root
Delete all involved users .Xauthority files.
If you've got hanging sessions left, manually execute x2goterminatesessions with the ID.
Make the x2goserver logging level to debug in /etc/x2go/x2xgoserver.conf
Reboot the machine.

Then open a new Master Session -> KDE or xterm, whatever..
Use the root command again to make sure it's known by the x2goserver.
Then start the Shadow Session to the Master Session.

Include as many logfiles as possible into a new mail to the mailing list. 

Greetings,
Kjellski



2013/7/17 Roland Giesler <roland@giesler.za.net>
Kjell, thanks for your input so far.  I was wondering if you have any
other suggestions to try and track this pesky problem down?

regards

Roland

On Mon, Jul 15, 2013 at 12:32 PM, Roland Giesler <roland@giesler.za.net> wrote:
> On Thu, Jul 11, 2013 at 8:07 PM, Kjell Otto <otto.kjell@gmail.com> wrote:
>> Have you tried to delete the .Xauthority File in the users Homefolder?
>
> I have now.
>
> On the client I log:
>
> Loop: PANIC! The remote NX proxy closed the connection.
> Loop: PANIC! Failure negotiating the session in stage '7'.
> Loop: PANIC! Wrong version or invalid session authentication cookie.
>
> On the server, the session log shows:
>
> running as X2Go Agent
>
> NXAGENT - Version 3.5.0
>
> Copyright (C) 2001, 2011 NoMachine.
> See http://www.nomachine.com/ for more information.
>
> Info: Agent running with pid '2543'.
> Session: Starting session at 'Mon Jul 15 11:50:05 2013'.
> Info: Proxy running in server mode with pid '2543'.
> Info: Waiting for connection from 'localhost' on port '30001'.
> Warning: Refusing connection from '192.168.1.3'.
> Error: Connection with remote host 'localhost' could not be established.
> Error: Aborting session with 'Unable to open display
> 'nx/nx,options=/home/roland/.x2go/C-roland-50-1373881804_stDUNITY_dp24/options:50''.
> Session: Aborting session at 'Mon Jul 15 11:50:55 2013'.
> Session: Session aborted at 'Mon Jul 15 11:50:55 2013'.
>
> This makes me think.  I port forward port 22 through the ADSL router
> (which has 192.168.1.1 as LAN ethernet address and the server has
> 192.168.1.3).  Could this have something to do with the problem?  What
> is port 30001 used for and should I allow that through the firewall?
> Surely port 22 should be enough?
>
> I have also turned apparmor off, but it makes no difference.
>
> thanks again
>
> Roland
>
>>
>> Please Try that first. Your log seems to be completely normal so far... Do
>> you have a Desktop you can shadow to? I mean if there is no MasterSession
>> opened, then you can't shadow it...
>>
>> Best regards,
>> Kjellski
>>
>>
>> 2013/7/11 Roland Giesler <roland@giesler.za.net>
>>>
>>> On Thu, Jul 11, 2013 at 9:22 AM, Kjell Otto <otto.kjell@gmail.com> wrote:
>>> > Hi Roland,
>>> >
>>> > have you seen what's mentioned here:
>>> >
>>> > http://developer.berlios.de/bugs/?func=detailbug&bug_id=18258&group_id=2978
>>>
>>> Here's what my server log has.
>>>
>>> Jul 11 15:14:54 Ashton /usr/bin/x2golistdesktops[30895]:
>>> x2golistdesktops has been called without options
>>> Jul 11 15:14:54 Ashton /usr/bin/x2golistsessions[30899]:
>>> x2golistsessions has been called with options: x2goserver
>>> Jul 11 15:14:58 Ashton /usr/bin/x2gostartagent: x2gostartagent called
>>> with options: 1440x900 adsl 16m-jpeg-9 unix-kde-depth_24 us pc105/us 1
>>> S 1XSHADrolandXSHAD:0
>>> Jul 11 15:14:58 Ashton /usr/bin/x2gosessionlimit[30961]:
>>> x2gosessionlimit has been called
>>> Jul 11 15:14:58 Ashton /usr/bin/x2golistsessions[30964]:
>>> x2golistsessions has been called with options: --all-servers
>>> Jul 11 15:14:59 Ashton /usr/bin/x2gofeature: x2gofeature called with
>>> options: X2GO_RUN_EXTENSIONS
>>> Jul 11 15:14:59 Ashton
>>> /usr/share/x2go/x2gofeature.d/x2goserver-extensions.features:
>>> x2goserver-extensions.features called with options:
>>> X2GO_RUN_EXTENSIONS
>>> Jul 11 15:15:00 Ashton /usr/bin/x2goserver-run-extensions:
>>> x2goserver-run-extensions called with options:
>>> roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24 pre-start
>>> Jul 11 15:15:00 Ashton /usr/bin/x2gostartagent: successfully started
>>> X2Go agent session with ID
>>> roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24
>>> Jul 11 15:15:00 Ashton /usr/bin/x2gofeature: x2gofeature called with
>>> options: X2GO_RUN_EXTENSIONS
>>> Jul 11 15:15:00 Ashton
>>> /usr/share/x2go/x2gofeature.d/x2goserver-extensions.features:
>>> x2goserver-extensions.features called with options:
>>> X2GO_RUN_EXTENSIONS
>>> Jul 11 15:15:00 Ashton /usr/bin/x2goserver-run-extensions:
>>> x2goserver-run-extensions called with options:
>>> roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24 post-start
>>> Jul 11 15:15:00 Ashton /usr/bin/x2gostartagent: blocking creation of
>>> agent's keyboard file
>>>
>>> /home/roland/.x2go/C-roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24/keyboard
>>> as requested by session startup command
>>> Jul 11 15:15:52 Ashton /usr/bin/x2goumount-session[31487]:
>>> x2goumount-session has been called with options:
>>> roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24
>>> Jul 11 15:15:54 Ashton /usr/bin/x2goumount-session[31524]:
>>> x2goumount-session has been called with options:
>>> roland-50-1373548499_stS1XSHADrolandXSHADPP0_dp24
>>> Jul 11 15:17:01 Ashton CRON[31876]: (root) CMD (   cd / && run-parts
>>> --report /etc/cron.hourly)
>>> Jul 11 15:19:46 Ashton /usr/bin/x2golistdesktops[428]:
>>> x2golistdesktops has been called without options
>>> Jul 11 15:19:46 Ashton /usr/bin/x2golistsessions[432]:
>>> x2golistsessions has been called with options: x2goserver
>>> Jul 11 15:19:52 Ashton /usr/bin/x2gostartagent: x2gostartagent called
>>> with options: 1440x900 adsl 16m-jpeg-9 unix-kde-depth_24 us pc105/us 1
>>> S 1XSHADrolandXSHAD:0
>>> Jul 11 15:19:52 Ashton /usr/bin/x2gostartagent: client announced
>>> itself as ,,105.237.13.183''
>>> Jul 11 15:19:52 Ashton /usr/bin/x2gostartagent: shadow session
>>> requested: mode 1, user: roland, desktop: :0
>>> Jul 11 15:19:52 Ashton /usr/bin/x2gosessionlimit[496]:
>>> x2gosessionlimit has been called
>>> Jul 11 15:19:52 Ashton /usr/bin/x2golistsessions[499]:
>>> x2golistsessions has been called with options: --all-servers
>>> Jul 11 15:19:52 Ashton /usr/lib/x2go/x2gogetdisplays[513]:
>>> db_getdisplays called, server: Ashton; return value:
>>> Jul 11 15:19:52 Ashton /usr/lib/x2go/x2gogetports[523]: db_getports
>>> called, server: Ashton; return value:
>>> Jul 11 15:19:53 Ashton /usr/lib/x2go/x2goinsertsession[550]:
>>> db_insertsession called, session ID:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24, server: Ashton,
>>> session ID: roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24
>>> Jul 11 15:19:53 Ashton /usr/lib/x2go/x2goinsertport[562]:
>>> db_insertport called, session ID:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24, server: Ashton, SSH
>>> port: 30001
>>> Jul 11 15:19:53 Ashton /usr/lib/x2go/x2goinsertport[574]:
>>> db_insertport called, session ID:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24, server: Ashton, SSH
>>> port: 30002
>>> Jul 11 15:19:53 Ashton /usr/lib/x2go/x2goinsertport[587]:
>>> db_insertport called, session ID:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24, server: Ashton, SSH
>>> port: 30003
>>> Jul 11 15:19:53 Ashton /usr/bin/x2gofeature: x2gofeature called with
>>> options: X2GO_RUN_EXTENSIONS
>>> Jul 11 15:19:53 Ashton
>>> /usr/share/x2go/x2gofeature.d/x2goserver-extensions.features:
>>> x2goserver-extensions.features called with options:
>>> X2GO_RUN_EXTENSIONS
>>> Jul 11 15:19:53 Ashton /usr/bin/x2goserver-run-extensions:
>>> x2goserver-run-extensions called with options:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24 pre-start
>>> Jul 11 15:19:53 Ashton /usr/bin/x2gostartagent: successfully started
>>> X2Go agent session with ID
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24
>>> Jul 11 15:19:53 Ashton /usr/bin/x2gofeature: x2gofeature called with
>>> options: X2GO_RUN_EXTENSIONS
>>> Jul 11 15:19:54 Ashton
>>> /usr/share/x2go/x2gofeature.d/x2goserver-extensions.features:
>>> x2goserver-extensions.features called with options:
>>> X2GO_RUN_EXTENSIONS
>>> Jul 11 15:19:54 Ashton /usr/bin/x2goserver-run-extensions:
>>> x2goserver-run-extensions called with options:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24 post-start
>>> Jul 11 15:19:54 Ashton /usr/lib/x2go/x2gocreatesession[680]:
>>> db_createsession called, session ID:
>>> roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24, cookie:
>>> 99946d36e5e8848f5f91951d5c1c6f67, client: xxx.yyy.13.183, pid: 645,
>>> graphics port: 30001, sound port: 30002, file sharing port: 30003
>>> Jul 11 15:19:54 Ashton /usr/bin/x2gostartagent: blocking creation of
>>> agent's keyboard file
>>>
>>> /home/roland/.x2go/C-roland-50-1373548792_stS1XSHADrolandXSHADPP0_dp24/keyboard
>>> as requested by session startup command
>>>
>>> That last line: Is that because of the error, or is it causing the error?
>>>
>>> thanks
>>>
>>> Roland
>>>
>>>
>>> >
>>> > Wether it helps or not, it would be great to see the server side of
>>> > this, so
>>> > please post the corresponding entries of your /var/log/syslog after
>>> > configuring the x2goserver for debugging(set it in
>>> > /etc/x2go/x2goserver.conf).
>>> >
>>> > Nevertheless, the only Cookies I can think used by x2go are the MIT
>>> > magic
>>> > cookies of X... maybe try to delete the .Xauthority of the user trying
>>> > to
>>> > log in and retry...
>>> >
>>> > Greetings,
>>> > @Kjellski
>>> >
>>> >
>>> > 2013/7/10 Roland Giesler <roland@giesler.za.net>
>>> >>
>>> >> I must have read every mailing list and other posts I could find on
>>> >> Google regarding this problem.  Nowhere was anyone able to identify
>>> >> the actual cause and fix for this problem.
>>> >>
>>> >> How can this be?  Does anyone know where the X2Go developer(s) hang
>>> >> out?
>>> >>
>>> >> thanks
>>> >>
>>> >> Roland Giesler
>>> >> +27 (0)72-450-2817
>>> >> http://www.giesler.za.net
>>> >>
>>> >> Disclaimer: The sender invokes the rule of "exemptus responsibilitus"
>>> >> pertaining to caffeine soluted inductions and/or decantations thereof
>>> >> into tactile communication interfaces and alternative apparatuses with
>>> >> respect to personal computation devices or otherwise implementations
>>> >> of electronic and/or bionic devices. This impartation is intended for
>>> >> the addressed party, unless conditions contrary to the aforementioned
>>> >> exist, in which case it is pertinent.  Reduce without further ado to
>>> >> nothingness said impartation; alternatively "refrain from traversing
>>> >> the point of origination, be not enriched by 200 Randus and proceed
>>> >> without delay to enjailment".
>>> >>
>>> >>
>>> >> On Thu, Jul 4, 2013 at 10:25 PM, Roland Giesler <roland@giesler.za.net>
>>> >> wrote:
>>> >> > bump.
>>> >> >
>>> >> > anyone with help?
>>> >> >
>>> >> > On Mon, Jul 1, 2013 at 11:36 PM, Roland Giesler
>>> >> > <roland@giesler.za.net>
>>> >> > wrote:
>>> >> >> This error is most annoying to say the least, since no-where on the
>>> >> >> internet is an explaination of the cause nor the fix for it.  Some
>>> >> >> people seem to have managed to get past it by luck.
>>> >> >>
>>> >> >> This is an Ubuntu 12.04 64bit server that had nxserver install.  One
>>> >> >> day (probably after some update, but it was too long ago to undo of
>>> >> >> trace now) the nxclient just stopped working.
>>> >> >>
>>> >> >> I left it after many futile attempt to fix it.  I have completely
>>> >> >> removed (purged) openssh-server and nxserver, nxnode and nxclient.
>>> >> >> Numerous times, apart from creating keys manually and more.
>>> >> >>
>>> >> >> So I though, let me switch to X2Go.  And lo and behold, I get the
>>> >> >> same
>>> >> >> error.
>>> >> >>
>>> >> >> Strangely enough though, I can connect perfect to the server via SSH
>>> >> >> every time.
>>> >> >>
>>> >> >> What causes this and how does one fix this please?
>>> >> >>
>>> >> >> regards
>>> >> >>
>>> >> >> Roland
>>> >> _______________________________________________
>>> >> X2Go-User mailing list
>>> >> X2Go-User@lists.berlios.de
>>> >> https://lists.berlios.de/mailman/listinfo/x2go-user
>>> >
>>> >
>>
>>