SSH Key Authentication Setup Guide

Introduction

I’ll guide you through setting up SSH key authentication for accessing our CS server (cs-ssh.uwf.edu). This method is both more secure and convenient than traditional password authentication, eliminating the need to enter your password each time you connect.

Key Concepts

Public Key Authentication

SSH key authentication uses a pair of cryptographic keys:

• Public Key: Like a padlock that you can freely share. It’s placed on the server you want to access.
• Private Key: Like the unique key that opens your padlock. Must be kept secret and secure on your computer.

Benefits

• Increased security through cryptographic strength
• No need to remember or type passwords
• Protection against brute-force attacks
• Automated secure file transfers and remote operations

Step-by-Step Instructions

1. Generate Your SSH Key Pair

Open a bash terminal and run:

ssh-keygen -t ed25519 -C "your_email@uwf.edu"

When prompted:

• Press Enter to accept the default file location
• Enter a passphrase (recommended) or press Enter twice for no passphrase

2. Verify Key Generation

Check that your keys were created:

ls ~/.ssh/

You should see two files:

• id_ed25519 (private key)
• id_ed25519.pub (public key)

3. Copy Public Key to Server

ssh-copy-id -i ~/.ssh/id_ed25519.pub your_username@cs-ssh.uwf.edu

4. Test Connection

Try connecting to the server:

ssh your_username@cs-ssh.uwf.edu

You should now connect without being prompted for a password.

Important Security Notes

• Never share your private key
• Keep your private key file secure (600 permissions on Unix-like systems)
• Back up your private key securely
• If using a passphrase, remember it can’t be recovered if forgotten