Add an SSH Key to GitHub

Generate, Configure, and Use SSH Keys for Seamless Git Operations

If you are working with Git and GitHub, using SSH keys for authentication is a secure and convenient way to push and pull code from your repositories without having to enter your username and password every time.

In this guide, I will walk you through the entire process of generating an SSH key on a Linux machine and adding it to your GitHub account. Whether you are setting up a new machine or improving your workflow, this guide is for you.

What is an SSH Key and Why Use It?

SSH (Secure Shell) keys are a pair of cryptographic keys used to authenticate secure connections between your computer and remote servers (like GitHub).

Benefits of using SSH with GitHub:

• Secure: Keys are more secure than using passwords.

• Convenient: Once set up, you won’t need to enter your GitHub credentials for each Git operation.

• Required: GitHub now requires SSH (or PATs) for operations involving remote repositories.

Step 1: Generate an SSH Key on Your Linux Machine

Open a terminal on your Linux machine and enter the following command:

ssh-keygen -t ed25519 -C "your_username@company_domain.com"

Explanation of the command:

• ssh-keygen: The command to generate a new SSH key.

• -t ed25519: Specifies the type of key to create. ed25519 is a modern, secure algorithm recommended by GitHub.

• -C "your_username@company_domain.com": Adds a comment (usually your email) to the key to identify it later.

You will be prompted to choose a file to save the key:

Enter file in which to save the key (/home/your_user/.ssh/id_ed25519):

What to do here:

• Press Enter to accept the default location (~/.ssh/id_ed25519).

• Next, you’ll be asked for a passphrase. This adds an extra layer of security.

Enter passphrase (empty for no passphrase):
Enter same passphrase again:

You can press Enter twice to skip setting a passphrase if you want passwordless authentication.

Once complete, you’ll see output like this:

Your identification has been saved in /home/your_user/.ssh/id_ed25519
Your public key has been saved in /home/your_user/.ssh/id_ed25519.pub

Step 2: Copy the Public Key

Now you need to copy your public key so you can add it to GitHub.

Run this command to display your public key:

cat ~/.ssh/id_ed25519.pub

This will output something like:

ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIC34xF0Y83a3JL7eJ4DndyT4KzVtqZ8o8uPOd4NmLd9G your_username@company_domain.com

Select the entire string and copy it to your clipboard. Make sure not to add extra spaces or line breaks when copying.

Step 3: Add the SSH Key to Your GitHub Account

Now, let’s add your key to GitHub:

1. Log in to your GitHub account.

2. In the top-right corner, click on your profile picture and then Settings.

3. In the sidebar, click on SSH and GPG keys.

4. Click the green New SSH key button.

Fill out the form:

• Title: Give your key a meaningful name (e.g., Spare laptop, Work Desktop, Ubuntu VM).

• Key: Paste the SSH key you copied earlier.

Click Add SSH key to save.

You may be prompted to confirm your GitHub password for security.

🎉 Success! You’re now connected to GitHub via SSH.