Ruby agent installation

[video link] For installation tips, watch this New Relic video (less than 1 minute).

Installing the gem

The New Relic Ruby agent's gem is available from as newrelic_rpm.

For applications using Bundler, just add the gem to the Gemfile:

gem 'newrelic_rpm'

If you're using Rails 3 or above, or Rails 2.3 in the recommended configuration, Rails will automatically call Bundler.require and cause newrelic_rpm to be required during startup of your application. If you're using Sinatra or another framework, you'll need to either manually call require 'newrelic_rpm', or call Bundler.require.

Note: In order to use automatic Browser Application Monitoring and Cross Application Tracing in a Rack application that does not use Sinatra or Rails, manually include additional middlewares provided by the agent. See Rack Middlewares.

Tip: Place the New Relic gem as low in the list as possible, allowing the frameworks above it to be instrumented when the gem initializes.

Installing the configuration file

After installing the agent:

  1. Copy the newrelic.yml file into the config sub-directory of your application.
  2. Change the default application name to a meaningful name.

You can download a fresh newrelic.yml that includes your license key from the Account settings when logged in to

Updating the agent

If you're using Bundler, run bundle update newrelic_rpm. Otherwise, run gem update newrelic_rpm.

Installing outside production environments

Typically you will install the New Relic Ruby agent in your production environment. If you want to try out the Ruby agent in a development or localhost environment, verify in the relevant environment: block of the newrelic.yml file that the monitor_mode config value has been set to true.

For example, to deploy New Relic in your development environment and still be able to view your app's performance metrics, in the development: block, set the monitor_mode config value to true. For more information about using New Relic's Ruby agent outside production environments, see Developer mode.

Uninstalling the Ruby agent gem

To uninstall the Ruby agent using Bundler, remove gem 'newrelic_rpm' from your Gemfile. If you are not using Bundler, remove all references to newrelic_rpm from your environment.rb file.

Installing on older versions of Rails

If you're installing the Ruby agent on Rails 2.x, and aren't using Bundler, use the instructions below.

Rails 2.1 - 2.3 without Bundler

  1. Install the gem using gem install newrelic_rpm.
  2. Edit environment.rb, and add to the initializer block: config.gem "newrelic_rpm".

Rails pre-2.1

New Relic does not officially support Rails versions prior to 2.1. However, if you want to use New Relic for Rails versions 2.0.*, edit environment.rb and add this statement after the initializer: block:

require "newrelic_rpm"

For more help

Additional documentation resources include:

  • Ruby agent configuration (general configuration settings, proxy, transaction tracer, error collection, and updates)
  • New Relic for Ruby (overview of compatibility and requirements, installation, configuration, troubleshooting, known issues, advanced features, and beta releases)
  • Updating deprecated Ruby agents (Ruby agent versions that New Relic no longer supports, how to verify the version your app uses, and how to ensure you have the most up-to-date version)

If you need additional help, get support at