Christoph Schmidt-Hieber | 9 Apr 14:54 2015
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X authorization issues

Dear all,

We're having issues connecting to an x2go server running on Debian
Wheezy. Specifically, we cannot connect to an xfce4 desktop from an OS
X client.

The x2go client version is 4.0.3.2 (from MacPorts).
The x2go server version is 4.0.1.19-0x2go2+git20150326.1064+wheezy.main.1
(from the x2go Debian repo)

Connections using plain "ssh -Y" or "ssh -X" work fine.

Connections with x2go to a single application work fine.

The permissions of $HOME/.Xauthority are 600

The owner of  $HOME/.Xauthority is $USER:$USER

The first attempt to connect will simply fail, without valuable error
messages (at least to me), the second attempt will result in:

"Your session was closed before reaching a usable state.
This can be due to the local X server refusing access to the client.
Please check authorization provided by the remote X application."

Debug output from the client is attached.

Any help would be greatly appreciated.

Christoph
(Continue reading)

Heng Zhou | 9 Apr 01:43 2015

GNOME and Unity can not launch

Hi,

I installed the latest X2Go client, but it only works with KDE. When I tried to launch Unity and GNOME desktop, they always fail. To be specific, when I selected Unity, the desktop just flashes and disappear. When I selected GNOME, I got a black desktop window and VcXsrv reports an error saying "Cannot establish any listening socket - make sure an X server isn't already running". The contents of VCXSrv.0.log is:

_XSERVTransSocketCreateListener: failed to bind listener
_XSERVTransSocketINETCreateListener: ...SocketCreateListener() failed
_XSERVTransMakeAllCOTSServerListeners: failed to create listener for inet6
_XSERVTransSocketCreateListener: failed to bind listener
_XSERVTransSocketINETCreateListener: ...SocketCreateListener() failed
_XSERVTransMakeAllCOTSServerListeners: failed to create listener for inet
(EE)
Fatal server error:
(EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE)
(EE) Server terminated with error (1). Closing log file.

I have no idea how to check if any X server is running on my computer. All the settings of X2Go are default. The remote machine is ubuntu 14.04. Any help? Thanks.
<div><div dir="ltr">
<div>Hi,</div>
<div><br></div>
<div>I installed the latest X2Go client, but it only works with KDE. When I tried to launch Unity and GNOME desktop, they always fail. To be specific, when I selected Unity, the desktop just flashes and disappear. When I selected GNOME,&nbsp;I got a black desktop window and VcXsrv reports an error saying "Cannot establish any listening socket - make sure an X server isn't already running". The contents of VCXSrv.0.log is:</div>
<div><br></div>
<div>_XSERVTransSocketCreateListener: failed to bind listener<br>_XSERVTransSocketINETCreateListener: ...SocketCreateListener() failed<br>_XSERVTransMakeAllCOTSServerListeners: failed to create listener for inet6<br>_XSERVTransSocketCreateListener: failed to bind listener<br>_XSERVTransSocketINETCreateListener: ...SocketCreateListener() failed<br>_XSERVTransMakeAllCOTSServerListeners: failed to create listener for inet<br>(EE) <br>Fatal server error:<br>(EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE) <br>(EE) Server terminated with error (1). Closing log file.<br>
</div>
<div><br></div>
<div>I have no idea how to check if any X server is running on my computer. All the settings of X2Go&nbsp;are default.&nbsp;The remote machine is ubuntu 14.04. Any help? Thanks.</div>
</div></div>
Mihai Moldovan | 9 Apr 01:17 2015
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Re: Fwd: Ctrl-s not recognised (OS X client)

On 08.04.2015 01:35 PM, Christopher Thomas wrote:
> I usually start emacs using a function that I have defined in my
> .bashrc file that puts it in the background automatically, since
> otherwise I often forget to do that. However the behaviour is the same
> if I simply type "emacs" from the command line. 
>
> However this problem is not confined to emacs. For example if I start
> LibreOffice then the usual save command Ctrl-s does nothing.

This hints at something else capturing the keypresses. So, emacs is
started by bash and bash naturally in a terminal, but what is this
terminal started from? A full desktop environment or the terminal
emulator as a single application in X2Go Client?

> Should I be trying to sort this out from the server end?  But as I
> said this is a university server so there is a limited amount I can do
> apart from contacting the administrators there. I have started the xev
> program from a terminal after logging in via x2go but I don't know how
> to interpret the output.

Starting up xev will likely put it into foreground and every X11 event
is printed out verbatim.

Make sure the pointer doesn't move, or you will be spammed with messages.

Pressing Ctrl will print a message with "Control_L" on the third line.

Afterwards, pressing "s" (hold Ctrl all the time) will print a message
having "s" in the third line and the fourth line will read XLookupString
gives 1 bytes: (13) "" if everything is working as expected.

Given that the key combination is not recognized in emacs and
LibreOffice, I suspect nothing will pop up in xev.

However, my basic test suggested that it's not a general X2Go problem,
as it's working on my machine(s) and I know a few users using
LibreOffice via X2Go. Naturally, Ctrl-S not working would be a grave
issue for them.

My current suspicion is that the keypresses are either captured by a
desktop environment or NX.

I understand that you have no control over the remote system as such,
but, if existent, what is the content of /etc/nxagent/keystrokes.cfg?

Mihai

On 08.04.2015 01:35 PM, Christopher Thomas wrote:
> I usually start emacs using a function that I have defined in my
> .bashrc file that puts it in the background automatically, since
> otherwise I often forget to do that. However the behaviour is the same
> if I simply type "emacs" from the command line. 
>
> However this problem is not confined to emacs. For example if I start
> LibreOffice then the usual save command Ctrl-s does nothing.

This hints at something else capturing the keypresses. So, emacs is
started by bash and bash naturally in a terminal, but what is this
terminal started from? A full desktop environment or the terminal
emulator as a single application in X2Go Client?

> Should I be trying to sort this out from the server end?  But as I
> said this is a university server so there is a limited amount I can do
> apart from contacting the administrators there. I have started the xev
> program from a terminal after logging in via x2go but I don't know how
> to interpret the output.

Starting up xev will likely put it into foreground and every X11 event
is printed out verbatim.

Make sure the pointer doesn't move, or you will be spammed with messages.

Pressing Ctrl will print a message with "Control_L" on the third line.

Afterwards, pressing "s" (hold Ctrl all the time) will print a message
having "s" in the third line and the fourth line will read XLookupString
gives 1 bytes: (13) "" if everything is working as expected.

Given that the key combination is not recognized in emacs and
LibreOffice, I suspect nothing will pop up in xev.

However, my basic test suggested that it's not a general X2Go problem,
as it's working on my machine(s) and I know a few users using
LibreOffice via X2Go. Naturally, Ctrl-S not working would be a grave
issue for them.

My current suspicion is that the keypresses are either captured by a
desktop environment or NX.

I understand that you have no control over the remote system as such,
but, if existent, what is the content of /etc/nxagent/keystrokes.cfg?

Mihai

Les Mikesell | 7 Apr 19:57 2015
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OSX/windows keyboards?

When I start a remote linux session from an OSX client, then
disconnect and pick up the session from a windows client, the screen
seems OK but the keyboard input is garbage.  I thought I had that
problem a long time ago and then it was fixed.   Do the client
versions have to stay in sync?   And is there some way to reset the
keyboard type to fix it and continue the session?

--

-- 
   Les Mikesell
     lesmikesell@...
Christopher Thomas | 7 Apr 01:54 2015
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Ctrl-s not recognised (OS X client)

Hi,

I connect to my university servers remotely from OS X using x2go. It seems that the keystroke combination Ctrl-s (and perhaps some other combinations) are not recognised. This is quite inconvenient, particularly since I use emacs extensively and Ctrl-s is the command for a search. I couldn't find any info on this problem. Can anyone help?

Chris 
<div><div dir="ltr">Hi,<div><br></div>
<div>I connect to my university servers remotely from OS X using x2go. It seems that the keystroke combination Ctrl-s (and perhaps some other combinations) are not recognised. This is quite inconvenient, particularly since I use emacs extensively and Ctrl-s is the command for a search. I couldn't find any info on this problem. Can anyone help?</div>
<div><br></div>
<div>Chris&nbsp;</div>
</div></div>
Robert Dinse | 5 Apr 05:52 2015

WorkSpace Switching


      I spoke too soon, the control-alt-left-arrow or control-alt-right-arrow
to switch workspaces when you have an x2go client in them works sometimes.
It seems to initially not work, but when you use control-alt-m to minimimize,
after it's restored, then the other keys work.  This is under Ubuntu with a
Matédesktop.

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
  Eskimo North Linux Friendly Internet Access, Shell Accounts, and Hosting.
    Knowledgeable human assistance, not telephone trees or script readers.
  See our web site: http://www.eskimo.com/ (206) 812-0051 or (800) 246-6874.

      I spoke too soon, the control-alt-left-arrow or control-alt-right-arrow
to switch workspaces when you have an x2go client in them works sometimes.
It seems to initially not work, but when you use control-alt-m to minimimize,
after it's restored, then the other keys work.  This is under Ubuntu with a
Matédesktop.

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
  Eskimo North Linux Friendly Internet Access, Shell Accounts, and Hosting.
    Knowledgeable human assistance, not telephone trees or script readers.
  See our web site: http://www.eskimo.com/ (206) 812-0051 or (800) 246-6874.
Robert Dinse | 4 Apr 08:19 2015

CTR-ALT- <- ->


      I noticed that at some point someone fixed x2go so my control-alt-left or 
control-alt-right arrows now switch work spaces as they do in remmina which
makes x2go SO much more useful to me.  Whoever made that fix, THANK YOU!

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
  Eskimo North Linux Friendly Internet Access, Shell Accounts, and Hosting.
    Knowledgeable human assistance, not telephone trees or script readers.
  See our web site: http://www.eskimo.com/ (206) 812-0051 or (800) 246-6874.
Robert Dinse | 3 Apr 21:38 2015

Centos 7


      Under CentOS 7

      I've updated to the latest kernel provided in the El Repo repository,

          kernel-ml.x86_64   3.19.3-1.el7.elrepo    <at> elrepo-kernel

      They have no version configured with pre-emption and this version without
does not provide smooth video over x2go, very jerky and laggy like the stock
kernel.

      If I build a kernel from source from kernel.org, even using the same
conf, and install it:

 	make clean; make; make modules_install install

      The entire process proceeds without error but it breaks something
horribly in grub and instead of a boot menu I get a pointer alignment error
when I try to boot, so I haven't been able to install a custom preemptive
kernel on this machine.

      The packaged kernels install fine, so it's got to be something different
with grub2 that the make file isn't doing.

      I've found instructions on the web for building custom kernels and they
recommend the above procedure which is the same as Centos6, but it does not
work for me.

      Anyone with any pointers?

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
  Eskimo North Linux Friendly Internet Access, Shell Accounts, and Hosting.
    Knowledgeable human assistance, not telephone trees or script readers.
  See our web site: http://www.eskimo.com/ (206) 812-0051 or (800) 246-6874.
Robert Dinse | 3 Apr 07:23 2015

Low Latency


On 04/02/2015 10:46 AM, Les Mikesell wrote:

     Someone recently posted on the x2go list that he had a problem with
     jerky videos playing remotely on Ubuntu, but solved it by installing a
     low latency kernel that was available as an alternative.  That made me
     curious as to whether CentOS has an equivalent - or a way to build
     something similar.

      Les, I can help you with CentOS 6 kernels but I haven't been successful
at installing a custom kernel on CentOS 7, for some reason after I update
grub2 then try to boot, I get a pointer alignment error and can't even get
the grub boot screen up.  But I have been successful with CentOS 6 and can
provide assistance if needed.

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
  Eskimo North Linux Friendly Internet Access, Shell Accounts, and Hosting.
    Knowledgeable human assistance, not telephone trees or script readers.
  See our web site: http://www.eskimo.com/ (206) 812-0051 or (800) 246-6874.
Mihai Moldovan | 2 Apr 23:34 2015
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Re: trouble connecting to server

On 02.04.2015 11:29 PM, Michael Stauffer wrote:
> Doh! OK I tried uninstalling gnome 3.10 so I could put an earlier
> version on. It's not working easily though. I"m just going to start
> over with centos 6.6 and that should work out of the box if I
> understand right, since it uses gnome 2.

IIRC, yes. But why not use CentOS 7 and for instance XFCE?

Mihai

Attachment (smime.p7s): application/pkcs7-signature, 5766 bytes
On 02.04.2015 11:29 PM, Michael Stauffer wrote:
> Doh! OK I tried uninstalling gnome 3.10 so I could put an earlier
> version on. It's not working easily though. I"m just going to start
> over with centos 6.6 and that should work out of the box if I
> understand right, since it uses gnome 2.

IIRC, yes. But why not use CentOS 7 and for instance XFCE?

Mihai

alb alb | 1 Apr 08:15 2015
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Session disconnect

Hi,
i have a little problem...
i have to viertual machines; one with ubuntu 10.04 and the other one with 14.04
i have installed x2gosharingdesktop in both and put them in a startup applications and activated default...but when i connect to them :
in the 10.04 ->  the sharingdesktop is still working and when i disconnect is estill active, and i can connect perfectly again.
in the 14.04 -> at the same time i connect to this machine, i can access perfectly the first time, but  the x2gosharingdesktop disappeared from active programs and when i disconect i can not connect again

thanks in advance,
Alb
<div><div dir="ltr">
<div>
<div>
<div>
<div>
<div>
<div>Hi, <br>
</div>i have a little problem...<br>
</div>i have to viertual machines; one with ubuntu 10.04 and the other one with 14.04<br>
</div>i have installed x2gosharingdesktop in both and put them in a startup applications and activated default...but when i connect to them :<br>in the 10.04 -&gt;&nbsp; the sharingdesktop is still working and when i disconnect is estill active, and i can connect perfectly again. <br>
</div>in the 14.04 -&gt; at the same time i connect to this machine, i can access perfectly the first time, but&nbsp; the x2gosharingdesktop disappeared from active programs and when i disconect i can not connect again<br><br>
</div>thanks in advance,<br>
</div>Alb<br>
</div></div>

Gmane