New Relic is a well-known tool to monitor servers and applications that has been upgraded to support Node. It is intended to be used by those looking to monitor the memory and CPU usage as well as things such as network activity and the health of your Node processes. In this section, we'll look into how to install it on your server and provide examples of its use.

Installation involves applying for a license key from the New Relic website at newrelic.com. Setting up your account is straightforward. After signing up, you'll be presented with a list of monitoring tools that New Relic provides—you'll want to select New Relic Servers. In the next steps, you'll select Node.js as your development environment and the OS you'll be working within. I'll use CentOS. After selecting your OS, you should see the installation instructions generated for you, with your license key included—just cut and paste.

You are installing and starting a server that will probe system processes...