Monitoring Rails applications with Datadog

This text provides a comprehensive guide on how to use Datadog to collect metrics, request traces, and logs from a Rails application running on Passenger, Apache, and MySQL. It covers the installation and configuration of the Datadog Agent, enabling APM for tracing requests across every service in your application, configuring log collection, setting up performance monitoring for Rails applications, capturing Passenger and Rails logs, enabling Datadog's Apache integration, and enabling Datadog's MySQL integration. It also discusses how to create custom dashboards and alerts using the collected data. The guide is written in a detailed manner with step-by-step instructions for each process.