Help with stu.cs.jmu.edu

“stu” is a server running Linux that is available to all students in the JMU Computer Science Department.

Logging in to stu

You can login to “stu” using an SSH client (and the host name stu.cs.jmu.edu). All modern operating systems should come with command-line SSH client (usually named ssh). Windows 10 users may need to install the client manually, depending on version and edition. GUI SSH clients are also available, but add little.

To log in, type the following in a terminal/cmd window, replacing <eid> with your JMU username.

  ssh <eid>@stu.cs.jmu.edu

Enter your password when prompted. Nothing will appear on the screen so type carefully!

Keypairs

You can avoid the need to authenticate yourself (with your eID and password) each time you login using a public/private key pair. This is particularly useful when using another protocol (e.g., Subversion or Git) on top of SSH.

Accessing Lab Computers

To log into a specific lab computer you first login to stu as normal and then ssh to a lab machine by hostname. The hostnames are based on the room and computer number and take the form “L[room_number][computer_number].cs.jmu.edu”.

Room Hostname Range
ISAT/CS 248 L248{01..32}.cs.jmu.edu
ISAT/CS 250 L250{01..33}.cs.jmu.edu
ENGEO 2204 L2204{01..32}.cs.jmu.edu

This can be simplified by using the -J option to ssh. For example, the following command would jump through stu to reach a lab computer in ISAT/CS 250.

  ssh -J <eid>@stu.cs.jmu.edu <eid>@l25005.cs.jmu.edu

You can do this transparently by adding the following to your ~/.ssh/config:

  Match !host stu.cs.jmu.edu host *.cs.jmu.edu !exec "nc -z -w 1 %h %p"
      ProxyJump stu.cs.jmu.edu

This uses netcat to determine if you can connect directly to the host and if not, for all .cs.jmu.edu hosts other than stu, jump through stu. Connecting to a lab machine with this configuration is the same from on or off campus: ssh l25005.cs.jmu.edu.

Setting up keypairs is highly recommended if you're doing this regularly to avoid multiple password prompts.

Transferring Files to and From stu

You can transfer files to “stu” using an SCP client (and the host name stu.cs.jmu.edu). Modern operating systems include a command-line scp client named scp. See this article for some usage examples. There are also GUI clients available that work like a file explorer. Options include WinSCP and Cyberduck.

If you want a more seamless experience or the ability to edit files on “stu” using a local editor like Eclipse or VS Code, you can mount your home folder locally. The department strongly discourages the use of editor-specific plugins such as “Visual Studio Code Remote” for performance and security reasons, and students found using these extensions may be asked to stop.

Using stu as an HTTP Server

You (should) have a directory named www in your home directory. Any file that you put in that directory will be available to the public as a “web page” (i.e., it will be served in response to an HTTP GET request) from the server w3stu.cs.jmu.edu under your e-ID.

For example, if Prof. Fakename (i.e., fakenazx) put a file named test.html in her www directory it would be accessible to the public using the URL as w3stu.cs.jmu.edu/fakenazx/test.html.

Of course, the HTTP server must have permission to read the file. So, the file must be world-readable.