Technical Resources

Technical Support

You can contact support by email at support AT cs DOT usfca DOT edu
Make sure to CC support in all your subsequent replies!

System Administrators

Elias Husary, Harney Science Center 408
Alex Fedosov, Harney Science Center 408

Hours: Monday-Friday 10:00 am - 6:00 pm

Frequently Asked Questions

Accounts

I am a new student. How do I get an account?
I am not able to log in to stargate! I keep getting "connection refused" error!
How do I change my password?
What is my quota? How do I know if I am over the limit? How do I free up space?

Lab Machines

Which machines can I login to?
I was able to log in locally in the lab earlier but now I can't login anymore!
How can I reboot HR 148 machines?
How can I reboot G12 machines?
How do I login to CS machines from home?
How can I transfer files to/from home?

Other

How do I sign up for class mailing lists?
How do I submit my projects?
Is it true that I can get free Microsoft software?
Can you install Linux on my laptop / home computer?
I need to buy a laptop. Do you have any recommendations?

Windows users

Can I install programming tools on Windows?
How do I access a command line on Windows?
Is the Windows command line the same as Linux?
How do I use Linux on my Windows 10 computer?
Can I install a Linux Desktop Environment on Windows 10?

Video tutorials

CS Basics and Concepts Fall 2020
What is ssh?
Copying files to a remote server

Q: I am a new student. How do I get an account?
A: If you enroll in a CS course, an account will be created for you automatically. Note that the CS account is separate from your main USF account -- the regular USF accounts do not work on CS machines. If you have not yet registered, but need to use your account in a CS class, e-mail support AT cs DOT usfca DOT edu or visit the CS Systems Administrators in HR 408.

Q: I am not able to log in to stargate! I keep getting "connection refused" error!
A:  If you enter your password incorrectly more than three (3) times, your IP address will get banned from stargate. This is done to reduce the number of brute-force attempts to break into your account, of which we are seeing thousands a day. If this happens to you, please e-mail support@cs.usfca.edu with your IP address, as reported by http://whatismyip.host/, and we will unban you.

Q: How do I change my password?
A: To change your Linux password: log in to Linux. Open up a terminal, type passwd, press ENTER, and follow the prompts.

Q: What is my quota? How do I know if I am over the limit? How do I free up space?
A: Your home directory should have an 8GB total capacity. To check how much space you've used, you can run:

Q: Which machines can I login to?
A: As a CS student, you can make use of any machine in the following labs: Harney 148 (Kudlick classroom), Harney 413 (PC Lab running Ubuntu), CSI G12
(G12 classroom)

Q: I was able to log in locally in the lab earlier but now I can't login anymore!
A: In some cases, this is due to your account being over quota. (i.e. you are using up too much disk space or you have too many files.) Even though you cannot login in GUI mode, you can still login in text mode (or using ssh) and delete files. Boot into Linux, press CTRL-ALT-F1, and type in your user name and password. (Or ssh into stargate.) If you are able to get in, see the response to the question about student quotas below, and follow the directions to check how much disk space you are currently using. If your quota is full, delete some files and try to login again in GUI mode. If your quota is not full and you still can't login, contact support.

Q: How can I reboot HR 148 (Kudlick) machines?
A: You can reboot them over the web at the following link: https://www.cs.usfca.edu/kudlick. Use your CS username and password to log in. This will also turn on a machine if it has been turned off.

Q: How can I reboot G12 machines?
A: You can reboot them over the web at the following link: https://www.cs.usfca.edu/g12. Use your CS username and password to log in. This will also turn on a machine if it has been turned off.

Q: How do I login to CS machines from home?
A: To access CS machines from home, connect to stargate.cs.usfca.edu via ssh, and from there on, to any available lab machine to work on your assignments.
Under Windows, we recommend using Windows built-in ssh from a command prompt. You can also install Windows Subsystem for Linux (WSL) and use ssh from there. 

Mac OSX has ssh built-in to its Terminal application.


If you would like to ssh to stargate without typing in a password every time you ssh to stargate, you'll need to setup ssh keys first. Then, once you're connected to stargate via ssh, access the ".ssh" directory in your home directory, create a file called "authorized_keys" if it doesn't already exist, then paste in the full contents of your PUBLIC rsa key. Keep the private key private for security reasons. 

If you are using a research machine,you can connect directly to it by using ssh -j:  

myhouse$ ssh -J stargate [name of research machine]

Q: How can I transfer files to/from home?
A: To transfer files to/from your machine at home, we recommend using:

Under Windows: WinSCP.
Under Linux: scp at the command line or gftp if you prefer a GUI tool. Alternatively, you can use shfs to mount your CS home directory on your home machine so that you can save your work directly to the CS server and not worry about copying files back and forth.
Under Mac OS X: scp from the command line, or the Fugu GUI client.

In all cases, connect to stargate.cs.usfca.edu using your CS username and password.

quota -s

from the terminal in linux and look at the entry for your home directory.

If you need to free up space, we suggest that you first empty your browser's cache, which in 99% of the cases solves the problem.

Q: How do I sign up for class mailing lists?
A: You can see what lists are available on the main groups page. Pretty much every course has a mailing list. You will typically be automatically added to the course mailing list when you enroll. If not, you can contact support or ask your instructor how they have chosen
to handle the mailing list for their course.

Q: How do I submit my projects?
A: In some cases, your instructor will ask you to submit your project by putting it into a so-called submit directory. This is a special directory that can only be accessed by you, the instructor, and the TA, if any. You can find your submit directory for a particular class (if it exists) under /home/submit/<class>/<username> under Linux in the labs. Your instructor may ask you to submit your projects to github instead, in which case you will need to make sure you have an git repository. Contact support if you need help setting up a repository. Lastly, some courses may have their own alternate method for submitting projects that is not listed here.

Q: Is it true that I can get free Microsoft software?
A: Yes, with restrictions: you can only use this software for your school work. Login to MyUSF.  On the Dashboard, click View All Apps.  Next, click Personal Software Purchases. Now, search for the software you need.

Q: Can you install Linux on my laptop / home computer?
A: Yes.

Q: I need to buy a laptop. Do you have any recommendations?
A: While we provide lab computers as resources for your class projects and homework, we highly recommend our students to have a laptop computer. This is also an excellent opportunity for you to learn to manage and maintain one of the most important tools in your career.
Listed below are suggested hardware specifications.

Platform:

If you are bringing a current computer, anything that meets the specs below will be sufficient to begin with. (Both PC and Mac would work for this.) If you are purchasing a new computer, we would recommend purchasing a Mac, due to its underlying Unix-based kernel and shell. If you are going to purchase a new computer, try to match these specs:
Minimum hardware recommendations:

MacBook Pro
16 GB RAM
512 GB SSD HD

You should also have a USB thumb drive (and associated dongle, if using a Mac) for transferring data between lab and personal computers.

Q: Can I install programming tools on Windows?
A: Yes. Many tools, such as editors, IDEs (Integrated Development Environments), interpreters, compilers and debuggers have Windows version. When you to to the website of the tool you want to use, please choose the Windows version to download and install.

Q: How do I access a command line on Windows??
A: Windows 10 has two command line applications. one is the regular command line and the other is PowerShell. You can access them using these instructions:

Open Windows 10 command prompt
Open Windows 10 PowerShell

Q: Is the Windows command line the same as Linux?
A: No. Windows 10 uses a command prompt and PowerShell. Both applications allow you to type commands in order to execute them.
Linux uses a shell to type and execute commands. These features are similar but the commands they use and how they implement them are different. For instance, on Windows, I can see directory contents by typing the dir command. On Linux, the equivalent command is ls.

Q: How do I use Linux on my Windows 10 computer?
A: You can see install the Windows Subsystem for Linux (WSL). This is a feature in Windows 10 that allows you to run a Linux bash shell while logged into Windows 10. This is similar to running a Linux operating system on top of Windows 10. The WSL environment and file system is distinct from your Windows 10 file system (although you can access your files on both systems). While files are available across the two systems, applications are not. This is because you essentially have two operating systems. Any programming tool or application that you want to use on WSL has to be installed on WSL.

Bear in mind that the basic WSL is only a bash shell...you can type commands, but there is no GUI or Desktop Environment.

If you would like to install WSL, please read the information at the following link carefully

Windows Subsystem for Linux Documentation

Q: Can I install a Linux Desktop Environment on Windows 10?
A: Yes. The Desktop Environment provides you with a GUI, icons for your computer hardware and software such as hard drives, optical drives, directories and folders and applications. To install a Desktop Environment on WSL:

Install Desktop Environment on WSL for Windows 10

 

Q: CS Basics and Concepts Fall 2020
A:  Below is the video for CS Basics and Concepts Fall 2020:

CS Basics and Concepts Fall 2020

 

Q: What is ssh?
A:  ssh allows you to make a secure connection from your local client to a remote host.  Here is a short video:

ssh_video

 

Q: Copying files to a remote server
A:  scp allows you to securely copy files from your local client to a remote host.  Here is a short video:

scp_video