Configure Multiple GitHub Accounts on a Single Computer

Here are step-by-step instructions for configuring and managing multiple GitHub accounts on a single computer, including SSH key setup and Git configuration:

Step 1: Generate SSH Keys for Each GitHub Account

1. Open your terminal.

2. Generate a new SSH key for the first GitHub account:

   SH

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

   When prompted, save the key with a unique name, e.g., id_rsa_first_account.

3. Generate a new SSH key for the second GitHub account:

   SH

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

   When prompted, save the key with a unique name, e.g., id_rsa_second_account.

Step 2: Add SSH Keys to the SSH Agent

1. Start the SSH agent in the background:

   SH

   eval "$(ssh-agent -s)"
   

2. Add the first SSH key to the SSH agent:

   SH

   ssh-add ~/.ssh/id_rsa_first_account
   

3. Add the second SSH key to the SSH agent:

   SH

   ssh-add ~/.ssh/id_rsa_second_account
   

Step 3: Add SSH Keys to GitHub Accounts

1. Copy the SSH key for the first account to your clipboard:

   SH

   pbcopy < ~/.ssh/id_rsa_first_account.pub
   

   If pbcopy is not available, you can use:

   SH

   cat ~/.ssh/id_rsa_first_account.pub
   

2. Log in to your first GitHub account and navigate to Settings > SSH and GPG keys > New SSH key. Paste the key and save.

3. Repeat the process for the second account:

   SH

   pbcopy < ~/.ssh/id_rsa_second_account.pub
   

   If pbcopy is not available, you can use:

   SH

   cat ~/.ssh/id_rsa_second_account.pub
   

4. Log in to your second GitHub account and navigate to Settings > SSH and GPG keys > New SSH key. Paste the key and save.

Step 4: Configure SSH to Manage Multiple Accounts

1. Edit the SSH config file:

   SH

   nano ~/.ssh/config
   

2. Add the following configurations:

   SH

   # First GitHub account
   Host github-first
     HostName github.com
     User git
     IdentityFile ~/.ssh/id_rsa_first_account
   
   # Second GitHub account
   Host github-second
     HostName github.com
     User git
     IdentityFile ~/.ssh/id_rsa_second_account
   

Step 5: Configure Git for Multiple Accounts

1. Set global Git configuration (if not already set):

   SH

   git config --global user.name "Your Name"
   git config --global user.email "your_email@example.com"
   

2. For repositories associated with the first account, set the local Git configuration:

   SH

   cd path/to/your/repository
   git config user.name "Your Name for First Account"
   git config user.email "your_email_first_account@example.com"
   

3. For repositories associated with the second account, set the local Git configuration:

   SH

   cd path/to/your/other/repository
   git config user.name "Your Name for Second Account"
   git config user.email "your_email_second_account@example.com"
   

Step 6: Clone Repositories Using the Correct SSH Host

1. For the first GitHub account, use:

   SH

   git clone git@github-first:username/repository.git
   

2. For the second GitHub account, use:

   SH

   git clone git@github-second:username/repository.git
   

Step 7: Push and Pull Using the Correct SSH Host

Git will automatically use the correct SSH key based on the configuration in the ~/.ssh/config file.

That's it! You have now configured and can manage multiple GitHub accounts on a single computer.