[X2Go-User] x2go fails with tcsh

[Frank Steiner]

Hi,

I was able to solve this. When I looked into the code, I saw that you
already to use "bash -c '...'" for all commands, so quoting shouldn't be
an issue.

But as the error message for tcsh was about
  Warning: Protocol mismatch or no X authentication data.
I started looking at xauth and found an interesting difference between
bash and tcsh as login shell.

For bash, these entries are added by x2gostartagent:

myhost/unix:59  MIT-MAGIC-COOKIE-1  e938deb788659f0bf8c99069d199aff6
myhost.ifi.lmu.de:59  MIT-MAGIC-COOKIE-1  e938deb788659f0bf8c99069d199aff6
myhost.ifi.lmu.de:59  MIT-MAGIC-COOKIE-1  e938deb788659f0bf8c99069d199aff6

For tcsh, I got those:
myhost.ifi.lmu.de/unix:58  MIT-MAGIC-COOKIE-1  7212fb8aa466de75ea0224a4d010f5e4
myhost.ifi.lmu.de:58  MIT-MAGIC-COOKIE-1  7212fb8aa466de75ea0224a4d010f5e4
myhost.ifi.lmu.de:58  MIT-MAGIC-COOKIE-1  7212fb8aa466de75ea0224a4d010f5e4

And that's the point! For some reason, x2go needs the cookie for
display "myhost/unix" at some point and "myhost.ifi.lmu.de/unix"
doesn't suffice.

Indeed, when I wrote a little bash script

#!/bin/bash
echo $HOSTNAME

and called it with "ssh myhost bash -c './testscript'", it echoed 
"myhost" with login shell bash, and "myhost.ifi.lmu.de" with 
login shell tcsh.

I'm not yet sure where this difference comes from, if it's deep inside
bash and tcsh or in some server-wide login scripts from SuSE (it
was not in the users dotfiles, we even removed them all).

Anwyay, I added "setenv HOSTNAME `uname -n`" to my .cshrc and:
x2go works :-)

To make that work for all our users I added 
  HOSTNAME=${HOSTNAME%%.*}
into x2gostartagent which doesn't harm if HOSTNAME is already
without the domain. So maybe you could add this to the next
release to help people running into the same issue.

cu,
Frank




-- 
Dipl.-Inform. Frank Steiner   Web:  http://www.bio.ifi.lmu.de/~steiner/
Lehrstuhl f. Bioinformatik    Mail: http://www.bio.ifi.lmu.de/~steiner/m/
LMU, Amalienstr. 17           Phone: +49 89 2180-4049
80333 Muenchen, Germany       Fax:   +49 89 2180-99-4049
* Rekursion kann man erst verstehen, wenn man Rekursion verstanden hat. *