With the recent upgrade to MacOS Sierra, the “-X” option to ssh to enable X11 forwarding may not work. If you receive the message:
"untrusted X11 forwarding setup failed: xauth key data not generated"
after a recent MacOS upgrade, and X11 forwarding does not work, you can resolve the issue by add the line “ForwardX11Trusted yes” to your ~/.ssh/config file on your Mac. This should allow X11 forwarding to work from the JHPCE cluster. You may still see the warning:
"Warning: No xauth data; using fake authentication data for X11 forwarding"
To eliminate this warning, add the line “XAuthLocation /usr/X11/bin/xauth” to your ~/.ssh/config file on your Mac.