SSH Key on Mac - Shell-Bash

SSH keys on Mac are a powerful tool for developers to securely access and authenticate with remote servers. In this guide, we will walk you through the process of generating and using SSH keys on your Mac using the command-line interface.

Prerequisites

Before we begin, make sure you have the following installed on your Mac:

• Terminal
• OpenSSH

You can check if you have OpenSSH installed by running the following command in your terminal:

ssh -V

If you have OpenSSH installed, you should see the version number in the output. If not, you can install it using Homebrew:

brew install openssh

Generating Your SSH Key

Step 1: Check for existing SSH keys

Before generating a new SSH key, you should check to see if you already have an existing one. You can do this by running the following command:

ls -al ~/.ssh

If you see files named id_rsa and id_rsa.pub, then you already have an SSH key pair, and you can skip ahead to the Adding Your Key to the SSH Agent section.

Step 2: Generate a new SSH key

To generate a new SSH key, run the following command:

ssh-keygen -t rsa -b 4096 -C "your_email@example.com"

This will start the key generation process. You will be asked to provide a file name for the key, and you can leave the default settings by pressing Enter to use the default file name id_rsa.

The key generation process will also ask for a passphrase to secure your private key. It’s a good practice to use a passphrase to keep your key secure. Make sure to choose a strong and memorable passphrase.

Adding Your Key to the SSH Agent

The SSH agent is a program that runs in the background and keeps your SSH keys securely in memory. By adding your SSH key to the SSH agent, you can avoid typing your passphrase every time you use your SSH key.

Step 1: Start the SSH agent

If you’re using macOS Sierra 10.12.2 or later, the SSH agent will automatically start when you log in to your Mac. If you’re using an older version of macOS, you can start the SSH agent by running the following command:

eval "$(ssh-agent -s)"

Step 2: Add your SSH key to the SSH agent

To add your SSH key to the SSH agent, run the following command:

ssh-add -K ~/.ssh/id_rsa

Copying Your Public Key

Now that you have generated and added your SSH key to the SSH agent, you can copy your public key to the server you want to access.

Step 1: Print the public key

To print your public key, run the following command:

cat ~/.ssh/id_rsa.pub

This will display your public key in the terminal.

Step 2: Add your public key to the server

Copy your public key from the terminal using Cmd+C, and then follow the instructions provided by the server to add your public key.

Conclusion

That’s it! You now know how to generate and use SSH keys on your Mac. SSH keys are a powerful tool for securely accessing and authenticating with remote servers. With SSH keys, you can avoid typing your password every time you access a server and keep your account secure.