FastX

FastX is a commercial solution that enables users to start an X11 desktop environment on a remote system.  It is available on the Rivanna frontends.  Using it is equivalent to logging in at the console of the frontend.

Using FastX for the Web

We recommend that most users access FastX through its Web interface.  To connect, point a browser to https://rivanna-desktop.hpc.virginia.edu

FastX Web login screen

After entering your account ID and Netbadge password, you will see a launch screen.

In this example, we have no pre-existing sessions so we must create one.  Click the Launch Session button.  This will bring up a screen showing the options.

FastX Web Launch

Most users will choose the MATE desktop.  Click on the green MATE icon.  Text showing the choice will appear in the box below it.

FastX Web launch MATE

Click the Launch button to start your session.  If you are running a popup blocker in your browser, a request will appear that you unblock this site.  Once you do so, you can click the button to continue to your session.  After a short wait, your desktop will appear.

FastX Web Desktop

The toolbar at the top controls FastX behavior.  If the desktop does not automatically expand to the browser screen, the user can click the double arrow.  The pushpin pins the toolbar to the screen. 

When you are done, you can log out by selecting Logout from the System menu.  This will terminate your FastX Web session.

FastX Web logout

If you close the browser tab with the desktop, your session will be suspended rather than terminated.  You can go back to the launch tab and click the thumbnail of your desktop.  To resume the session, click the arrow (play) button.

FastX Web resume

To terminate the session, either select Terminate from the Actions dropdown menu, or click the close symbol.  Please terminate sessions if you do not plan to use them in the near future.

Using the Client

Users who wish to use a client local to their personal computer can install a client and connect through that.

Installation

You can download the file for your operating system on our website by clicking here.

On Macs you should also install XQuartz.  You will need the UVa Anywhere VPN client to use the FastX client from off Grounds.

Creating a Connection

When you open the software you will see a mostly blank screen.

screen shot

To set up a new connection profile, click the + icon.

Fast X Screen shot

Select ssh as the connection method.

Fast X Screen Shot

We recommend that you always use a named frontend so that you can reconnect to old sessions, rather than accidentally creating multiple sessions on multiple frontends. Choose...

rivanna1.hpc.virginia.edu

rivanna2.hpc.virginia.edu

rivanna3.hpc.virginia.edu

Example:
Name: rivanna1
Host: rivanna1.hpc.virginia.edu
User: mst3k
Don't change the Port, sci or FIPS entries.

Save

The system will respond with "This host is not recognized," click Continue.  Type your Eservices password.

Select the + icon again.

Fast X Screen Shot

Choose Gnome or xterm.  We are using Gnome for this example.

When the desktop appears you are logged on.  You can navigate starting from your home folder, or from Places. 

You can access multiple workspaces in this version of Gnome by clicking in the lower right.

Moving your mouse to the far upper left will bring up Activities and another view of the workspaces.

When you are done with your session you can move your cursor to the top middle of the screen to bring up the FastX menu.  The stop (||) icon will terminate the session.

Alternatively, you can dismiss the Gnome window and stop it at the "camera," or in the FastX menu.

If your session is interrupted you can reconnect by starting FastX and double-clicking on the session name.

Once you have saved a session, when you open FastX you will see a pane with your options.  Double-clicking a session will bring up the pane where you can choose Gnome or a terminal.

Using FastX with an Interactive Job (ijob)

Using FastX you can run applications that use a graphical user interface (GUI) such as Rstudio, the Matlab desktop, or other such programs on the frontends.  If you wish to run a graphical user interface for a problem that will require more memory or time than is permitted on the frontend, you may run it through an interactive job (an ijob). In the FastX desktop, start a terminal and run

ssh -Y $HOSTNAME

ijob -A <myacct> -p <partition> -t <time> -c 1

Once your interactive job has begun you will have a login shell on the remote node; you may then start your graphical program as usual.  We recommend ending the commmand with an ampersand (&) to return the prompt.For example, to use Rstudio, once your job has started, run

module load matlab
matlab &

Troubleshooting

If FastX disconnects, it will display a message box offering you the option to see details. Click this button and scroll all the way to the bottom of the text box that will open. If you see Error 1, it is a network problem. If you see Error 254 it is a problem of too many logins/processes, which means you probably have too many unterminated sessions. If you have too many logins you may try to kill your processes. Check which frontend you are using. Log in with an SSH client.

If you are using Windows and you do not already have a plain SSH client, download SecureFX from ITS, or download the free PuTTY or MobaXterm.

On Mac OSX you can use the built-in SSH command-line client. Open a Terminal and type

ssh mst3k@rivanna1.hpc.virginia.edu

If you are able to connect, run

kill -9 -1

to kill all your processes on that frontend.  If you are not able to connect please contact us for assistance.