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This guide covers a complete, production-ready Node.js deployment pattern: PM2 keeping your app running reliably, and Nginx as a reverse proxy handling public traffic and SSL.

Prerequisites

• Node.js installed (see How to Install Node.js on Ubuntu & Debian)
• Nginx installed
• A Node.js application ready to deploy

Step 1 — Transfer Your Application

rsync -avz ./myapp/ deploy@YOUR_SERVER_IP:/var/www/myapp/

Step 2 — Install Dependencies on the Server

cd /var/www/myapp
npm install --production

Step 3 — Install PM2 Globally

npm install -g pm2

Step 4 — Start Your Application with PM2

pm2 start app.js --name myapp

For apps with an npm start script:

pm2 start npm --name myapp -- start

Step 5 — Configure PM2 to Start on Boot

pm2 startup
pm2 save

pm2 startup generates and displays a command to run — copy and execute it exactly as shown to register PM2 with systemd.

Step 6 — Configure Nginx as a Reverse Proxy

sudo nano /etc/nginx/sites-available/myapp

server {
    listen 80;
    server_name myapp.example.com;

    location / {
        proxy_pass http://127.0.0.1:3000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

sudo ln -s /etc/nginx/sites-available/myapp /etc/nginx/sites-enabled/
sudo nginx -t && sudo systemctl reload nginx

Step 7 — Add HTTPS

sudo certbot --nginx -d myapp.example.com

Managing Your Application

pm2 list
pm2 logs myapp
pm2 restart myapp
pm2 reload myapp

pm2 reload performs a zero-downtime restart for apps running in cluster mode.

Running Multiple Instances (Cluster Mode)

pm2 start app.js -i max --name myapp

-i max automatically scales instances to match available CPU cores, distributing load across them.

Deploying Updates

cd /var/www/myapp
git pull
npm install --production
pm2 reload myapp

Common Errors

502 Bad Gateway — the app isn't running or crashed; check pm2 logs myapp.

App doesn't survive a reboot — confirm pm2 startup and pm2 save were both run correctly.

WebSocket connections fail — verify the Upgrade/Connection headers are present in the Nginx config.

Best Practices

• Bind your Node.js app to 127.0.0.1, not 0.0.0.0, so it's only reachable through Nginx
• Use PM2's cluster mode for CPU-bound applications to utilize multiple cores
• Always run pm2 save after any change to which apps PM2 manages

Related Articles

• How to Install Node.js on Ubuntu & Debian (with NVM)
• Nginx as a Reverse Proxy for Node.js/Docker Apps
• How to Install Let's Encrypt SSL with Certbot (Nginx & Apache)