FastX for Mac or Windows

Tags linux ssh X11

FastX - remote graphical display from Unix/Linux servers

FastX is a commercial tool for rendering graphical output from remote Unix/Linux servers.  It is a faster alternative to traditional remote display using the X11 protocol.   Software on the remote system writes to a virtual display, which is mapped to the desktop display using a protocol more like a video stream than X11.  FastX displays may be disconnected and reconnected while not interrupting the remote processes.

Software that is optimized for local display on a Linux workstation, such as rstudio, can have much higher performance using FastX, or may be completely incompatible with traditional remote X11. FastX is recomended for the graphical interfaces to rstudio, matlab, mathematica, idl, SAS, stata, spss, and similar software.

FastX uses an installed client with SSH, or display in a web browser (not yet available on Research ITC servers), and it can only be used with a remote computer that has the FastX server installed.  These include Andes, Polaris and Discovery.  Licensing is by number of concurrent connections.  

Clients are available for Windows, Macintosh, Apple's iPad or Linux workstations.


  1. Download FastX   The latest version may also be downloaded directly from Starnet.

  2. Mac:  copy the from the mounted DMG file to Applications. You may need to use Option+drag to force a copy rather than create a shortcut. 

  3. Windows: install the MSI file.  The nonroot .exe file can be used without admin privileges on the system.

  4. All clients: after installing FastX, click + in the inital connections screen and select SSH, then populate the boxes as shown in the example below. Leave the port at 22, and ignore the Sci line. The Name is anything you like - it will appear in the connections menu for future reference. User is your username on the remote system, usually your NetID.

  6. You will be prompted for a password, and then presented with a window as shown below.  FastX supports GSSAPI, so if you have already authenticated with the same username (NetID) on your desktop, you will not need to re-enter your password.

  7. Click the "+" button in upper right.

  8. Select xterm for a single Terminal window, which emulates a traditional command line SSH session. or GNOME to launch a complete set of Linux desktop processes (not recommended).  Your connection window will now show an active connection to the remote host.

  9. In the xterm window, start remote applications as usual. You will probably want to explicitly background applications with graphical interfaces, e.g. matlab &


Disconnecting vs Logging out

  • Explicit logout in the Xterm window or from a GNOME desktop will remove the connection.
  • Clicking the 'X' at the right side of the connection line will kill that connection (and any processes currently running in it), and remove the connection.
  • Quitting FastX without logging out or killing the connections will disconnect your local display but leave the session and processes running on the remote server.  You can then reconnect to the session later or from a different computer.  Clicking on a connection will re-establish the remote display to that session on the remote computer.
Beware that unintentionally disconnecting FastX with running processes will leave those processes using memory, and possibly CPU cycles and application licenses on the remote system.  They will also tie up a FastX license.  Unless you explicitly need to disconnect a session and return to it later, please always log out of the remote system before quitting FastX.  In particular, disconnected GNOME desktopns leave a large memory footprinton the remote system.



Article ID: 81595
Mon 6/24/19 6:04 PM
Thu 9/10/20 12:19 PM