title: Ruby on Rails : is IP port 3000 locked out for external access, on Rails 4.2?
body: <p>I run 2 versions on my RoR application on my computer:
  One is for demos (stable state, RoR 4.0), the other one is for development (RoR 4.2).
  Both versions can be accessed using <a href="http://localhost:3000" rel="nofollow">http://localhost:3000</a>.</p>
  
  <p>But I noticed an annoying difference: The Demo version can be accessed from another computer on the network. The Dev version cannot.
  This will be a big trouble when the Dev version is stabilized and becomes the Demo. My customer wants to test on his own laptop, through the wlan.</p>
  
  <p>Is there a "firewall" feature newly implemented ? 
  Is it one of my Gems ?</p>
  
  <p>I would be glad if someone can explain to me this changed behaviour !</p>
  
  <p><strong>Server is Webrick WEBrick 1.3.1 for both environments.
  Here are my gem files:</strong></p>
  
  <p><strong><em>Development (not accessible from another computer)</em></strong></p>
  
  <pre><code>source 'https://rubygems.org'
  ruby '2.2.0'
  
  gem 'rails', '~&gt; 4.2.0'
  gem 'bootstrap-sass', '~&gt; 3.3.3'
  gem 'sass-rails',   '~&gt; 5.0.1'
  gem 'coffee-rails', '~&gt; 4.1.0'
  gem 'uglifier', '~&gt; 2.7'
  gem 'bcrypt', '~&gt; 3.1.10'
  gem 'jquery-rails', '~&gt; 4.0.3'
  gem 'turbolinks', '2.5.3'
  gem 'jbuilder', '~&gt; 2.2.6'
  gem 'bootstrap-datepicker-rails', '~&gt; 1.3.1'
  gem 'will_paginate', '~&gt; 3.0.7'
  gem 'bootstrap-will_paginate', '~&gt; 0.0.10'
  gem 'selenium-webdriver', '~&gt; 2.44.0'
  gem 'sequenced', '~&gt; 2.0.0'
  gem 'annotate', '~&gt; 2.6.5'
  gem 'rspec-rails', '~&gt; 3.2.0'
  gem 'capybara', '~&gt; 2.4.4'
  gem 'factory_girl_rails', '~&gt; 4.5.0' 
  
  group :doc do
    gem 'sdoc', '0.3.20', require: false
  end
  
  # gem for dev and test only
  group :development, :test do
    gem 'pg'  
  end
  
  # gem for ORACLE POC
  group :ORACLE do
    gem 'ruby-oci8', '~&gt; 2.1.7'
   gem 'activerecord-oracle_enhanced-adapter', github: 'rsim/oracle-enhanced', branch: 'rails42'
  #  gem 'activerecord-oracle_enhanced-adapter', '~&gt; 1.5.5'
  end
  
  # gem for production
  group :production do
    gem 'rails_12factor'
    gem 'pg'
  end
  </code></pre>
  
  <p><strong><em>Demo (can be accessed from external computer)</em></strong></p>
  
  <pre><code>source 'https://rubygems.org'
  ruby '2.0.0'
  
  gem 'rails', '~&gt; 4.0.0'
  gem 'bootstrap-sass', '2.3.2'
  gem 'sass-rails',   '~&gt; 4.0.0'
  gem 'coffee-rails', '~&gt; 4.0.0'
  gem 'uglifier', '2.1.2'
  gem 'bcrypt', '~&gt; 3.1.0'
  gem 'jquery-rails', '~&gt; 3.0.4'
  gem 'turbolinks', '1.3.0'
  gem 'jbuilder', '1.4.2'
  gem 'bootstrap-datepicker-rails'
  gem 'will_paginate', '3.0.4'
  gem 'bootstrap-will_paginate', '0.0.9'
  gem 'selenium-webdriver', '2.42.0'
  gem 'sequenced'
  
  group :doc do
    gem 'sdoc', '0.3.20', require: false
  end
  
  # gem for dev and test only
  group :development, :test do
    gem 'pg'
    gem 'annotate', '2.5.0'
    gem 'rspec-rails', '2.14.0'
    gem 'capybara', '2.1.0'
    gem 'factory_girl_rails', '4.2.0'
  end
  # gem for ORACLE POC
  group :ORACLE do
    gem 'ruby-oci8', '~&gt; 2.1.0'
    gem 'activerecord-oracle_enhanced-adapter', '~&gt; 1.5.0'
    gem 'annotate', '2.5.0'
    gem 'rspec-rails', '2.14.0'
    gem 'capybara', '2.1.0'
    gem 'factory_girl_rails', '4.2.0'
  end
  
  # gem for production
  group :production do
    gem 'rails_12factor'
    gem 'pg'
  end
  </code></pre>
  
  <p>Thanks for your help !</p>
  
  <p>Fred</p>