mjhjmtu

I have read a bunch of similar questions on this site and others, but all of them either didn't reflect my situation or didn't provide a working solution.

So I have a Debian stretch x64 server running in a virtual KVM machine. I have installed Cygwin on Windows 7 Pro x64 and would like to run X applications on the Debian machine, using the Cygwin X server at the Windows machine.

This is my server-side SSH daemon configuration (Debian side):

AcceptEnv LANG LC_*
AllowAgentForwarding no
AllowTcpForwarding no
AllowStreamLocalForwarding no
ChallengeResponseAuthentication no
Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes256-ctr
Compression no
DebianBanner no
HostKeyAlgorithms ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-rsa,ssh-ed25519
KbdInteractiveAuthentication no
KexAlgorithms curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
ListenAddress 192.168.20.12:22
LoginGraceTime 20
MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com
PasswordAuthentication no
PermitUserRC no
Protocol 2
PubkeyAcceptedKeyTypes ssh-rsa,ssh-ed25519
RekeyLimit 100M 20m
Subsystem sftp /usr/lib/openssh/sftp-server
TCPKeepAlive no
X11Forwarding yes
X11UseLocalhost yes

This is the batch file I use to start konsole on the server (Windows side):

set CYG=c:cygwin64

%CYG%binrun.exe XWin -multiwindow -resize -clipboard -listen inet :1
SET DISPLAY=:1
SET LANG=en_US.UTF-8
%CYG%binssh.exe -f -Y root@192.168.20.12 "LANG=en_US.UTF-8 konsole"
"C:Program Files (x86)cmdowcmdow.exe" X-Morn-multiwindow /HID
exit

In principle, this works: When executing this batch file, konsole starts in a window on my Windows desktop. But there are two error messages in the cmd window:

libGL error: No matching fbConfigs or visuals found
libGL error: failed to load driver: swrast

As a last resort, I could live with those errors because konsole (and the other applications I need) obviously actually work, but I really would prefer knowing what is going on there (i.e. what causes the error messages).

From reading the other questions / threads / blog entries I have mentioned above, I got the impression that the problem might be related to missing nvidia or mesa components. So I installed some of these components on the Debian server doing (as root):

aptitude install libgl1-mesa-glx libgl1-glvnd-nvidia-glx

Indeed, when I then ran the batch file mentioned above, the libGL errors were not thrown any more. But unfortunately, now the konsole window did not appear on the Windows desktop any more.

After uninstalling the two packages again, the konsole window again appeared when I ran my batch file - of course, this is true for the libGL error messages as well.

I would like to understand both of the phenomena. So what could be the cause of the libGL error messages (given the fact that missing mesa or nvidia drivers or libraries should not play a role when running X applications via SSH), and why does installing the two packages mentioned above keep the konsole windows from appearing?

Once again, all other questions I saw were relating to situations where the OP wanted to start X applications locally, i.e. wanted to run them on the same machine where the X server ran, or did not have a solution which was working in my case.

The problem went away after installing the following packages (apt has installed them together):

• dbus-x11


• libglib2.0-tests


• libdbus-glib-1-2


• libgee-0.8-2


• libmoonshot1

I can't tell for sure which of these packages (or which combination thereof) made the problem go away. I do not plan to do further examinations because this machine has become a production server in the meantime.

However, I think I can give an educated guess:

• 
  libgee-0.8-2 and libmoonshot1 do not have anything to do directly with the low-level X11 or UI parts, so I am quite sure that they are out of the game.


• 
  libglib2.0-tests (as the name implies) is just a test suite for GLib, so I am quite sure that this is out of the game as well.


• I really can't tell which of the remaining two candidates might have solved the problem. I have the feeling that the problem was more related to GLib than to X11, so my favorite is libdbus-glib-1-2. But this is really just a feeling ...

It would be nice if somebody in the same situation (i.e. setting up a Debian stretch server and running X applications via SSH) could confirm this. But even when not, I think this answer is useful because exactly this question has been asked at other places dozens of times without a solution having been given (to my best knowledge).