X Forwarding is the term for running software on a remote Unix-flavor machine (such as scc1.bu.edu) while displaying the graphics (interface and resulting images) to ones local machine (such as a Windows desktop). This functionality is useful for applications such as MATLAB or IGV, that require a graphical user interface. It is possible to do on all major operating systems but the difficulty of doing so varies. Please consult the appropriate section for your operating system:

Select your operating system


An X-Server can be installed and configured on a Microsoft Windows system in a few different ways. This section will focus on the MobaXterm application, which was used in the SSH and FTP guides, for simplicity. Other software options are listed below

X-Forwarding Clients

Viewing Graphics using MobaXterm

  • MobaXterm has an X-server built-in, so after you login to the SCC you should be able to launch a remote graphical application without any extra work.
  • To check that the X-server is working properly, type xclock at the command prompt and hit “Enter”:
        scc1% xclock
    A new graphics window showing an analog clock should appear on your desktop:
  • Close the window to return the command prompt.

Apple OS X

Following the release of OS X 10.8 support for X11 was removed from the OS X operating system. If your computer is running 10.8 “Mountain Lion” or any newer version of OS X and you have never used X11 or X-forwarding on your computer, you will need to download and install XQuartz before continuing.

Viewing Graphics on OSX

  1. Hold the <command> key down with your left hand and press the space bar with your right hand; type “XQuartz” followed by the key. If nothing comes up, you must first install the XQuartz/X11 application, which is available at http://xquartz.macosforge.org/landing/. Newer versions of the Mac OS do not automatically include it. Make sure you install the XQuartz package associated with your particular version of the Mac operating system. To find out the version number of your operating system, click on the apple icon in the upper-right hand corner of the screen, and then “About This Mac.” 
  2. In the terminal, enter “ssh -Y yourBULoginName@scc1.bu.edu”. Don’t forget the “-Y” option or it won’t work. Next, hold down the <command> key with your left hand and press the “N” key with your right. This action will open a new X11 capable terminal window.
  3. Type exit in the terminal when you are done working on the SCC.


    • X Forwarding should be built-in on your Linux machine but you will need to include the -X flag with your ssh command.
      your_local_machine% ssh –X yourBULoginName@scc1.bu.edu
    • To test that your display is working properly, you can run a simple graphical application to display an analog clock:
      scc1% xclock&
      If you don’t see a clock, then you either forgot to use the –X (capital X) flag to ssh above or you have an issue with your local graphical setup.
For a “Remote Desktop” like function on the SCC please see the VNC page. VNC may speed up some graphical applications, but for the majority of people this is probably not necessary.