I was running the standard checks that Arno gave us to make sure everything is up and running on my computer. I discovered that I couldn’t run “xterm” while connected to lxplus.cern.ch I received the error “xterm Xt error: Can’t open display:”
Thanks to some help from Elim, I found out I was connected via “ssh user@lxplus.cern.ch” whereas I needed to be connected to “ssh -X user@lxplus.cern.ch”. Sure enough, I connected to ssh -X and was able to run “xterm” without a problem.
If you’re having problems with running “xterm”, try this out and see if it works.
Michael
maybe try -XY, since that’s what he told us to do.. Just to be safe and to prevent future problems.
just -X worked for me too.
typing “man ssh” into the terminal will bring up a list of all the possible tags as well as the additional info.
It says,
“-X Enables X11 forwarding. This can also be specified on a per-host
basis in a configuration file.
X11 forwarding should be enabled with caution. Users with the
ability to bypass file permissions on the remote host (for the
user’s X authorization database) can access the local X11 display
through the forwarded connection. An attacker may then be able
to perform activities such as keystroke monitoring.
For this reason, X11 forwarding is subjected to X11 SECURITY
extension restrictions by default. Please refer to the ssh -Y
option and the ForwardX11Trusted directive in ssh_config(5) for
more information.
-x Disables X11 forwarding.
-Y Enables trusted X11 forwarding. Trusted X11 forwardings are not
subjected to the X11 SECURITY extension controls.”