To use SSH for CI/CD in GitHub Actions, you need to generate an SSH key pair and add:

• The private key to your GitHub repo secrets.
• The public key to your server’s authorized keys.

Here’s how to do it:

✅ 1. Generate SSH Key Pair on Your Local Machine

Run this in your terminal (Linux/macOS/git bash/WSL):

ssh-keygen -t ed25519 -C "github-deploy"

If your system doesn’t support ed25519, you can use:

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

When prompted:

• Enter file name: You can name it something like ~/.ssh/github_cicd
• Passphrase: Leave empty (press Enter) for automation

✅ 2. Copy the Public Key to Your Server

ssh-copy-id -i ~/.ssh/github_cicd.pub deployuser@your.server.ip

Replace deployuser with the actual username on your server and your.server.ip with your server IP or domain.

If ssh-copy-id isn't available, do this manually:

cat ~/.ssh/github_cicd.pub

Copy the output and add it to:

~/.ssh/authorized_keys

on your server.

✅ 3. Add the Private Key to GitHub

1. Open your private key:

cat ~/.ssh/github_cicd

1. Copy the entire content (including -----BEGIN OPENSSH PRIVATE KEY----- and -----END OPENSSH PRIVATE KEY-----).

2. Go to your GitHub repository → Settings → Secrets and variables → Actions → New repository secret.

3. Name: SSH_PRIVATE_KEY
   Value: (paste the private key)

✅ 4. Use the Key in GitHub Actions

Your GitHub Actions file is already using this with:

- name: Set up SSH
  uses: webfactory/ssh-agent@v0.7.0
  with:
    ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }}

That’s it — GitHub will now be able to SSH into your server during deployment.