title: Rails server is running, but cannot connect to localhost:3000
body: <p>I am learning Ruby on Rails with railstutorial.org
  I had set everything up and working fine from Chapter 1. However, all of a sudden my next app has an issue.</p>
  
  <p>I run "rails server"</p>
  
  <pre><code>=&gt; Booting WEBrick
  =&gt; Rails 3.2.9 application starting in development on http://0.0.0.0:3000
  =&gt; Call with -d to detach
  =&gt; Ctrl-C to shutdown server
  [2012-11-15 00:45:08] INFO  WEBrick 1.3.1
  [2012-11-15 00:45:08] INFO  ruby 1.9.3 (2012-11-10) [x86_64-linux]
  [2012-11-15 00:45:08] INFO  WEBrick::HTTPServer#start: pid=2752 port=3000
  </code></pre>
  
  <p>Seems to be working fine, just like with my previous app.</p>
  
  <p>However, I try connecting to localhost:3000 , 0.0.0.0:3000 , 127.0.0.1:3000 on various browsers and they all cannot establish a connection to the server.</p>
  
  <p>Some things to note:</p>
  
  <p>-I was able to connect to localhost just a while ago--it just seems like it suddenly stopped working out of the blue.</p>
  
  <p>-My first app was working perfectly fine, but now it doesn't work for my first app either.</p>
  
  <p>-I don't have firewalls blocking the port, and my hosts file is not the problem.</p>
  
  <p>-I am on Ubuntu 12.10</p>
  
  <p>I almost always find solutions via search, but not this time.. so I need some help please. It's very frustrating as I feel like it's a simple problem that I spent way too long being stuck on.</p>
  
  <p>Thank you.</p>