Access SSH server - Mac/Linux

Follow these instructions to access Lehigh's SSH server using a terminal on computers running macOS or Linux.

1. Open the terminal application

Mac:

1. Click the Launchpad icon  in the Dock, type terminal in the search field, then click Terminal.

Linux: 

1. Press Ctrl+Alt+T in Ubuntu, or press Alt+F2, type gnome-terminal, and press the Enter key
2. If neither of those commands work, run an web search using your favorite search engine on how to open terminal for your specific Linux distribution

2. Connect to ssh.lehigh.edu

1. Enter the following command to connect to the Lehigh SSH server:

   ssh <your LU username>@ssh.lehigh.edu

Replace <your LU username> with your Lehigh username (e.g. xyz123)

3. Type yes to continue connecting if authenticity of host can't be established

1. If this is the first time connecting to the SSH server from your computer, you may see the following message (example below is shortened)...

   The authenticity of host 'ssh.lehigh.edu (128.180.6.102)' can't be established.
   ECDSA key fingerprint is ... 
   Are you sure you want to continue connecting (yes/no)?

2. Type yes and press the Enter key

3. You will then see a message confirming that the SSH server was added to the list of known hosts.

4. Enter your Lehigh password

• You'll be prompted for your Lehigh password
  • The password prompt is "silent", meaning you won't see your password as you type it

If you are on-campus or connected to the VPN

1. Enter your password; the connection should be successful
   
   1. If you enter your password incorrectly, you'll be prompted to enter your password again
   2. Multiple incorrect password attempts will eventually lock you out from being able to connect to the SSH server. If this happens, you will need to wait 24 hours before you are able to log in again.

If you are off-campus, not connected to the VPN, and have DUO enabled on your account

• 1. Enter your password then see next step below for DUO authentication

5. DUO authentication

This only applies to users who have DUO authentication enabled and are off-campus & not connected to the VPN.

1. You'll be prompted to enter a number that corresponds to the DUO authentication method you wish to use
2. Type a number for the authentication method you want to use and then press the Enter key
3. You'll get a corresponding DUO prompt; you must respond to the prompt to sign-in
4. After successful DUO authentication, you will be connected to the SSH server.

SSH key authentication

If you're interested in using SSH key authentication, see this LTS Research Computing page for instructions on how to get started: SSH public-key authentication