Logging Into KLC

Logging Into KLC#

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://klc0202.quest.northwestern.edu:3300/

http://klc0203.quest.northwestern.edu:3300/

http://klc0301.quest.northwestern.edu:3300/

http://klc0302.quest.northwestern.edu:3300/

http://klc0303.quest.northwestern.edu:3300/

http://klc0304.quest.northwestern.edu:3300/

http://klc0305.quest.northwestern.edu:3300/

http://klc0306.quest.northwestern.edu:3300/

http://klc0307.quest.northwestern.edu:3300/

http://klc0401.quest.northwestern.edu:3300/

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.

FastX also has desktop client available. It can have better performance over web browser access. Detailed instructions can be found on the NU IT Knowledge Base - Connecting to Quest with FastX.

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 a specific KLC node (for instance KLC0202), you would simply open Terminal and type:

ssh your-netid@klc0202.quest.northwestern.edu

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

ssh -Y your-netid@klc0202.quest.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 version of your Mac, you might need to install the free XQuartz application before X11 forwarding will work.

ssh client - Windows Instructions#

Kellogg Windows computers do not include an SSH client by default. We recommend installing one yourself — MobaXterm is a popular choice with a solid free version. Note that support for MobaXterm is not provided by Research Support or KIS; consider the Pro version if you need technical help. Other options include SecureCRT, PuTTY, and Cygwin.

Common instructions for using ssh clients (may differ slightly for different clients):

  • In the Sessions menu, select SSH.

  • In Remote Host, give the address of the server (e.g. any KLC login node address: klc0202.quest.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.

  • If you work on remote servers regularly, you will find it convenient to save and label a set of commonly used sessions.

Passwordless SSH Login 🔐#

Why Set Up Passwordless SSH Login?#

Passwordless SSH login allows you to securely access remote servers without typing your password each time. It uses SSH key pairs (public/private keys) for authentication instead of passwords.

Benefits:#

  • Convenience: No need to repeatedly enter passwords when logging in or running automated tasks.

  • Security: Stronger authentication using cryptographic keys, reducing the risk of brute-force attacks.

  • Automation: Essential for running scripts, transferring files, or syncing data across servers without manual intervention.

  • Faster Access: Speeds up workflows for data analysis, code deployment, or managing remote jobs.

Instructions#

  1. Generate an SSH key pair
    Run the following command on the Terminal app on macOs or Command Prompt/PowerShell on Windows:

    ssh-keygen -t rsa

    After running this, two files are created in your ~/.ssh directory:

    File

    Description

    id_rsa

    Your private key (keep this secure and never share it)

    id_rsa.pub

    Your public key (safe to share with servers)

  2. Copy the public key id_rsa.pub to KLC

    On macOS or Linux:

    • Run the following command on the Terminal:

      ssh-copy-id your_netid@klc0202.quest.northwestern.edu

    Add manually (work for all OS):

    • On your local machine, open id_rsa.pub in a text editor and copy its contents.

    • Open an SSH session to KLC, create the .ssh directory if it doesn’t exist:

      mkdir -p ~/.ssh

    • Then paste the contents of id_rsa.pub into the file:

      nano ~/.ssh/authorized_keys

  3. Update permission on KLC

    • Open an SSH session to KLC, update permission

      chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys
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