What is an X server, and why do I need one?

Graphical programs under Linux (apps that open their own window, as opposed to command-line programs) can run on one machine, but display on another.

This is a lot faster than screen-sharing apps like VNC, Remote Desktop or Team Viewer, because it doesn't have to send the entire contents of the screen.

Windows and Mac computers can display these X11 programs (as they're known), but do require extra software to be installed, known as an X server.

Installing an X server

On Windows

For Windows machines, install VcXsrv.

You can configure the server manually by running Xlaunch from the Start menu, or as a shortcut:

• Download config.xlaunch
• In Windows Explorer, type %APPDATA%/Microsoft/Windows/Start Menu/Startup into the address bar, and hit Enter
• Copy the downloaded folder into the window.
• The X server will now launch when Windows starts up
• (double-click the file to launch it now)

On Mac

For Mac computers, we recommend you install XQuartz.

Just open the .dmg file and run the installer inside - there's nothing else to do.

Testing your X server

On Mac or windows running WSL, run ssh -Y z1234567@login.cse.unsw.edu.au (subsituting your own zID)

On Windows running PuTTY, you'll need to configure it:

• In the Settings screen, go to Connection -> SSH -> X11, and tick the box labelled 'Enable X11 forwarding'.
• Then return to the 'Session' tab and click 'Save' to save this as the default.
• Now connect to login.cse.unsw.edu.au as normal.

Once you're logged in, run xeyes from the prompt.

If everything is working correctly, a window should appear with a pair of cartoon eyes following the mouse cursor around the screen.