You have two basic choices for how to connect to a remote server such as KLC.


One option is to use a secure shell (ssh) client. An ssh client will usually give you the option of working either with a point-and-click graphical interface or through a plain-text command line interface. Which ssh client you use depends on whether you are connecting from a Windows or a Mac computer.

Alternatively, you can use FastX as a simple way to get a graphical interface. With FastX, you could open Stata on KLC directly through your web browser, for example, and the experience would be much like running Stata on your personal computer.


ssh client - Windows Instructions

Kellogg Windows computers do not come with a pre-installed ssh client. So you will need to choose one and install it yourself. Research Support staff like to use MobaXterm, which has a very good free version. Because neither Research Support nor KIS can support the MobaXterm application, you should consider purchasing their pro version in order to access technical support. Other popular ssh clients include SecureCRT, PuTTY, and Cygwin.
The image below shows how you can set up a connection to KLC using MobaXterm.

  • In the Sessions menu, select SSH.
  • In Remote Host, give the address of the server (klc.northwestern.edu.)
  • Specify your NetID as the username.
  • Under Advanced SSH settings, check the box for X11-Forwarding if you want a graphical interface; leave it unchecked for a plain text interface.
Notice in the example above, we have previously defined several user sessions. Some use X11 forwarding while others do not. Some connect to the KLC load balancer while others connect to specific nodes. Still others connect to different sessions, such as WRDS. If you work on remote servers regularly, you will find it convenient to save and label a set of commonly used sessions.

ssh client - Mac Instructions

Mac computers come with a the Terminal program already installed as a standard program. To create a "plain" (not graphical) connection to the least busy KLC node, you would simply open Terminal and type:

ssh your-netid@klc.northwestern.edu

If you prefer a graphical (X11) interface, just add the -Y option:

ssh -Y your-netid@klc.northwestern.edu

Occasionally you might receive an error that says something like "host key verification failed." Most of the time, you can fix these problems by deleting your host key file and trying again:

rm ~/.ssh/known_hosts

Note: Depending on the vintage of your Mac, you might need to install the free XQuartz application before X11 forwarding will work.


FastX Browser Instructions

Getting a FastX graphical interface to a KLC server is as simple as putting your web browser to one of these server addresses. 

http://klc.northwestern.edu:3000           ...is the load balancer, and the individual nodes are at:

http://klc01.ci.northwestern.edu:3000 http://klc02.ci.northwestern.edu:3000 http://klc03.ci.northwestern.edu:3000 http://klc04.ci.northwestern.edu:3000 http://klc05.ci.northwestern.edu:3000 http://klc06.ci.northwestern.edu:3000

  • After you log in with your NetID and password, click the "Launch Session" button, and then select the application you want to run. By default, the sessions you start through the FastX web client will persist indefinitely - until either you terminate the session or the server is restarted. 
  • If you need to find a session you launched previously, you can find it on the My Sessions tab, but you must be logged on to the same KLC node where that session was launched! Therefore, we advise you to remember the specific node you are on if you intend to run very long jobs on KLC. We also advise you to Terminate sessions (under the Actions button in My Sessions) when you are done with your session.

Which One Should You Use?

Here are a few considerations to keep in mind when choosing whether to use ssh or FastX.

Graphical interfaces are slower than plain text interfaces are. If you open a program with X11, it might take a few seconds to load when the non-X11 version would load almost instantly. Like the name implies, 
FastX is relatively fast compared to other X11 tools. So FastX is a wise choice if you want a graphical interface.

Most ssh clients come with file transfer (sftp) capability built into them. With FastX, however, you will need to install and use a separate program (like Cyberduck) in order to move files to and from the KLC servers.

In general, we suggest becoming comfortable making ssh connections and using the command line, at least occasionally. Although point-and-click interfaces are convenient and intuitive, relying on graphical interfaces will present challenges to the future reproducibility of your work.  

Kellogg School of Management