Generating and Configuring SSH Key Pairs
Follow the steps below to configure a new SSH key pair in anticipation of accessing a cluster with SSH. Once you have generated and configured your SSH key pair for the cluster, you do not have to do this step each time.
Note: These instructions are written generally for OpenSSH and some programs, such as VS Code, are not compatible with this configuration using alternative SSH solutions like PuTTY.
| title | OpenSSH Compatible Client Required |
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PuTTY
is not supported).
If you do not have administrative access to the device you are connecting with, such as campus lab and office locations, please simply log in using the connection steps above and use your NetID/password combination.
Step 1 - Generate SSH Key Pair
First, you'll need to create and configure an SSH pair for each node you'll be connecting to, a great secure solution to connection.
Open a Terminal
Open a terminal based on your operating system.
- Windows - Command Prompt or Git Bash
- MacOS or Linux - Terminal
Generate the SSH Key Pair
In the terminal, generate your SSH key pair with the following command. Be sure to give the key pair a comment that allows you to identify it. This could be your email address, netid, cluster name, etc.
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# Example Key Generation ssh-keygen -o -a 100 -t ed25519 -f ~/.ssh/id_ed25519 -C "<comment; ex.netid or email cluster-name>" |
You'll be prompted to choose a location to save the key pair. This will default to '~/.ssh/id_ed25519'. Be sure to notate if you choose another location.
You also have the option be prompted to set a passphrase. While this is not 'required', utilize a passphrase is highly encourage in the effort to keep your private key secure. If you prefer to not, simple hit 'Enter' to skip.
| Warning | ||||
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| While you are not 'required' to utilize a passphrase, doing so is highly encourage in the effort to keep your private key secure
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Users should take all possible steps to secure their private keys, including utilization of a passphrase. Additionally, users should also avoid sharing their private key or passphrase with others, only keep their keys in secure storage locations, and consider rotating their SSH keys and update authorized keys on your connections to limit the impact in the event of compromise. |
Step 2 - Add the SSH Public Key to the Cluster
Next, you'll need to add the public key to each node you intend to connect to using this key noting that you can certainly generate a new key for each node. Being by displaying and copying your
Copy the Public Key
Use a corresponding terminal to display the public key so that you can copy it.
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# CMD type %USERPROFILE%\.ssh\id_ed25519.pub # Shell cat ~/.ssh/id_ed25519.pub |
Add the Public Key to the Login Node
Next, connect to the cluster and add the public key. Repeat this step for other nodes as needed.
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# Make the .ssh directory in your home directory mkdir -p ~/.ssh # Put the copied public key into your authorized_keys file echo "your_copied_public_key" >> ~/.ssh/authorized_keys # Ensure the .ssh locations have the correct permissions chmod 700 ~/.ssh chmod 600 ~/.ssh/authorized_keys |
Step 3 - Configure SSH Connection
Lastly, you'll need to ensure your application is configured to make the SSH connection utilizing your new or existing SSH key pair.
Either during connection prompt or when configuring, you'll need to know where your SSH configuration is saved. This is likely '~/.ssh/config' or 'C:\Users\<netid>\.ssh\config'.
Next, be sure the information for your host has been given the appropriate notations including specifying the SSH key location to be used.
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# Example Host Connection Configuration Host its-og-login1.syr.edu HostName its-og-login1.syr.edu User <your-netid> IdentifyFile <SSH key location, ex. "~/.ssh/id_ed25519"> |
Be sure to save any configuration files if you've made any changes.
Connect to the SSH Host
Finally, connect to your host. To do so, press 'F1' to open the Command Palette.
In the Command Palette, this time type 'Remote-SSH: Connect to Host...' and select it.
You should now see the intended host. Select it and you should be connect.
SSH Key Pair Compatibility
Below is a list of known compatible SSH solutions with this configuration type.
Getting Help
Question about Research Computing? Any questions about using or acquiring research computing resources or access can be directed at researchcomputing@syr.edu.