If you're deploying code to a Linux server (VPS) from a private GitHub repository, you can't just git pull directly. GitHub will deny access unless you set up secure authentication.

In this guide, we'll show you how to configure a dedicated user, set up SSH keys, and connect your VPS to GitHub using Deploy Keys — the safest way to pull private repo code.

🔐 Step 1: Create a Dedicated Deploy User

Instead of using root, let’s create a non-root user for deployment:

sudo adduser deployer

This will prompt you to set a password. You can skip other fields by pressing Enter.

📁 Step 2: Grant Access to Your Project Folder

Assume your project is at /var/www/myapp.

You can either:

✅ Option 1: Give full access to deployer

sudo chown -R deployer:deployer /var/www/myapp

🔐 Option 2 (Recommended): Use Group-Based Access

This is safer if multiple users access the server.

sudo usermod -aG www-data deployer
sudo chown -R www-data:www-data /var/www/myapp
sudo chmod -R 775 /var/www/myapp

🔑 Step 3: Generate SSH Key Pair (Deploy Key)

Log in as the deployer user or your current user and run:

ssh-keygen -t rsa -b 4096 -C "github-deploy"

When it asks for a filename, save as:

~/.ssh/id_rsa_github

You now have two files:

  • id_rsa_github → Your private key
  • id_rsa_github.pub → Your public key

Verify them:

cat ~/.ssh/id_rsa_github
cat ~/.ssh/id_rsa_github.pub

🔗 Step 4: Add the Public Key as a GitHub Deploy Key

  1. Go to your GitHub repo.
  2. Click Settings > Deploy Keys > Add Deploy Key.
  3. Give it a name (e.g., VPS deploy).
  4. Paste the contents of id_rsa_github.pub.
  5. ✅ Check "Allow write access" if needed.
  6. Click Add key.

⚙️ Step 5: Configure SSH to Use This Key

Back on your server, configure SSH to use the key with GitHub:

nano ~/.ssh/config

Paste this:

Host github.com
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_rsa_github

Save and exit.

✅ Step 6: Test the Connection

Run:

ssh -T git@github.com

You should see something like:

Hi username/repo! You've successfully authenticated...

🎉 That means your server can now securely pull from your private repo.

📥 Step 7: Clone or Pull the Repo

Now you can run:

git clone git@github.com:your-username/private-repo.git

Or if the repo already exists:

git pull origin main

✅ Done!

You’ve now securely connected your VPS to GitHub using SSH Deploy Keys.

This setup:

  • Keeps access limited
  • Avoids storing passwords or GitHub tokens
  • Makes your deployment safer and more manageable

In the next post, we’ll automate this process using GitHub Actions, so your server pulls updates automatically when you push code. 🔄

This is the second part of our deployment series: