title: ERROR -- ddtrace: [ddtrace] Failed to open TCP connection to localhost:8126 (Connection refused - connect(2) for "localhost" port 8126)
body: <p>I am currently working on a ruby on rails project that I have not deployed. While working in a development environment, every time I run <code>rails console</code> or the server I get the full error message:</p>
  
  <pre><code>ERROR -- ddtrace: [ddtrace] (/Users/stevenaguilar/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/ddtrace-0.8.0/lib/ddtrace/transport.rb:73:in `rescue in post') Failed to open TCP connection to localhost:8126 (Connection refused - connect(2) for "localhost" port 8126)
  </code></pre>
  
  <p>I thought I get around this issue by changing the configuration to work only in production.
  <code>config/initializers/datadog-tracer.rb</code></p>
  
  <pre><code>Rails.configuration.datadog_trace = {
    auto_instrument: true,
    auto_instrument_redis: true,
    default_service: 'my-rails-app'
  }
  </code></pre>