title: A server is already running. Check …/tmp/pids/server.pid. Exiting - rails
body: <pre><code>..$ rails s
  =&gt; Booting WEBrick
  =&gt; Rails 4.0.4 application starting in development on http://0.0.0.0:3000
  =&gt; Run `rails server -h` for more startup options
  =&gt; Ctrl-C to shutdown server
  A server is already running. Check /home/..name/rprojects/railsapp/tmp/pids/server.pid.
  Exiting
  </code></pre>
  
  <p>what is the easiest way to solve this for a rails beginner?</p>