SSH Key Generation for GitLab: A Team-Friendly Guide Print

This guide provides a straightforward process for creating and using a dedicated SSH key for GitLab on both Windows and Linux-based systems (including macOS and WSL).

1. Generate a New SSH Key

It's a best practice to create a new, uniquely named key for each service you use. We'll name our key id_gitlab.

For Windows (CMD / PowerShell)

1. Open Command Prompt or PowerShell.

2. Run the following command to start the key generation process:Bash

   ssh-keygen -t ed25519 -C "gitlab-enlivensupport" -f %USERPROFILE%\\.ssh\\id_gitlab

3. When prompted, you can enter a secure passphrase. This adds an extra layer of security. Press Enter to skip.

This creates two files in your C:\\Users\\YourName\\.ssh\\ folder:

• id_gitlab ???? (Your private key - never share this!)
• id_gitlab.pub ???? (Your public key - this is what you give to GitLab)

For Linux, macOS, or WSL (Windows Subsystem for Linux)

1. Open your terminal.

2. Run this command:Bash

   ssh-keygen -t ed25519 -C "gitlab-enlivensupport" -f ~/.ssh/id_gitlab

3. When prompted, enter a secure passphrase or press Enter to leave it empty.

This creates two files in your /home/your-user/.ssh/ directory:

• ~/.ssh/id_gitlab ???? (Your private key)
• ~/.ssh/id_gitlab.pub ???? (Your public key)

2. Add Your Public Key to GitLab

Now, you need to tell GitLab about your new key.

1. Copy your public key's content.

   • On Windows: Bash

     type %USERPROFILE%\\.ssh\\id_gitlab.pub

   • On Linux/macOS/WSL: Bash

     cat ~/.ssh/id_gitlab.pub

2. Select and copy the entire output, which starts with ssh-ed25519...

3. In GitLab, navigate to your profile:

   • Click your avatar in the top-right corner → Edit profile.
   • On the left sidebar, click SSH Keys.
   • Paste your key into the "Key" box, give it a "Title" (e.g., "Work Laptop"), and click Add key.

3. Configure SSH to Use Your New Key

Because you used a custom key name, you need to tell SSH when to use it. The best way is with an SSH config file.

1. Open or create the SSH config file.

   • On Windows (PowerShell): PowerShell

     if (-not (Test-Path $env:USERPROFILE\\.ssh\\config)) { New-Item $env:USERPROFILE\\.ssh\\config } notepad $env:USERPROFILE\\.ssh\\config

   • On Linux/macOS/WSL: Bash

     touch ~/.ssh/config

     nano ~/.ssh/config

2. Add the following configuration block: This tells SSH to automatically use your id_gitlab key whenever you connect to gitlab.com.Ini, TOML

   Host gitlab.com

   HostName gitlab.com

   IdentityFile ~/.ssh/id_gitlab

   IdentitiesOnly yes

   Note: On Windows, SSH understands the ~/ path correctly, so you can use the same text.

3. Save the file and exit the editor.

4. Test Your Connection

Finally, verify that everything is configured correctly.

Bash

ssh -T git@gitlab.com

If successful, you will see a "Welcome..." message from GitLab. You're now ready to clone, pull, and push to your repositories using SSH!

Bonus: How to Add Your Public Key to a Server for SSH Login

To access a remote server using your new key, you need to copy your public key to it.

Method 1: The Easy Way (ssh-copy-id)

If you're on Linux, macOS, or WSL, this is the recommended method.

Bash

ssh-copy-id -i ~/.ssh/id_gitlab.pub username@server_ip

Example:

Bash

ssh-copy-id -i ~/.ssh/id_gitlab.pub root@164.68.119.179

This command automatically appends your public key to the /root/.ssh/authorized_keys file on the remote server with the correct permissions.

Method 2: The Manual Way

If ssh-copy-id isn't available (like on Windows CMD), follow these steps.

1. Get your public key's content. Bash

   cat ~/.ssh/id_gitlab.pub

2. Copy the entire ssh-ed25519... line.

3. SSH into your remote server using your existing password method.Bash

   ssh username@server_ip

4. On the remote server, run the following commands to append your key and set the correct permissions: Bash

   Create the .ssh directory if it doesn't exist

   mkdir -p ~/.ssh

   Append your public key to the authorized_keys file

   echo "PASTE_YOUR_PUBLIC_KEY_HERE" >> ~/.ssh/authorized_keys

   Set correct, secure permissions

   chmod 700 ~/.ssh

   chmod 600 ~/.ssh/authorized_keys

5. Exit the server and try logging in again. It should now use your key instead of asking for a password.