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How can I tell if X11 port forwarding is set up?
One way you can easily verify if X11 forwarding is set up properly is to execute the following when logged into the cluster:
$ > echo $DISPLAY
If X11 forwarding is set up properly then this command should display a string like "tunic6.uit.tufts.edu:xx.0". Where xx is a number, perhaps 10, 11, 12,etc... If X11 forwarding is not set up properly then it will just return a blank line.
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