config/initializers/newrelic_stfu.rb

newrelic_stfu.rb

# NewRelic really wants me to know when it's not running. I don't care.
module NewRelic
  class Control
    module Frameworks
      class Rails
        def log_with_quieting!(msg, level=:info)
          log_without_quieting!(msg, level) \
            unless msg == "New Relic Agent not running."
        end
        alias_method_chain :log!, :quieting
      end
    end
  end
end