Node.js is a popular runtime environment that allows you to run JavaScript code outside of the browser. It is widely used for building scalable and high-performance applications. PM2 is a process manager for Node.js applications that ensures uptime and helps with monitoring and management.

In this guide, we will go through the steps to install Node.js and PM2 on Ubuntu 20.04.

Step 1: Update System Packages

Before installing Node.js and PM2, update your package list to ensure you have the latest versions available:

sudo apt update && sudo apt upgrade -y

Step 2: Install Node.js

There are multiple ways to install Node.js on Ubuntu 20.04. We will use the NodeSource repository to get the latest stable version.

Install Node.js via NodeSource

  1. Add the NodeSource repository:
    curl -fsSL https://deb.nodesource.com/setup_18.x | sudo -E bash -

    Replace 18.x with the latest LTS version if necessary.

  2. Install Node.js and npm:
    sudo apt install -y nodejs
  3. Verify the installation:
    node -v
npm -v

    This should output the installed versions of Node.js and npm.

Step 3: Install PM2

PM2 is a process manager that helps keep your Node.js applications running.

  1. Install PM2 globally using npm:
    sudo npm install -g pm2
  2. Verify the installation:
    pm2 -v

    This should return the installed version of PM2.

Step 4: Run a Node.js Application with PM2

To demonstrate PM2, we will create a simple Node.js application and run it.

  1. Create a sample application:
    mkdir myapp && cd myapp
echo "console.log('Hello from Node.js!');" > app.js
  2. Start the application using PM2:
    pm2 start app.js
  3. List running processes:
    pm2 list
  4. Save the process list so that it restarts on system reboot:
    pm2 save
  5. Enable PM2 to start on boot:
    pm2 startup

    Follow the instructions provided by the command to complete the setup.

Step 5: Monitor and Manage Applications

PM2 provides various commands to manage and monitor applications:

  • Restart an application:
    pm2 restart app.js
  • Stop an application:
    pm2 stop app.js
  • Delete an application from PM2:
    pm2 delete app.js
  • View logs:
    pm2 logs

Conclusion

You have successfully installed Node.js and PM2 on Ubuntu 20.04. With PM2, you can ensure that your Node.js applications run continuously, restart automatically, and provide useful logs for debugging. This setup is ideal for production environments where uptime and stability are crucial.