title: When RubyGems hangs
body: <p>I just had RubyGems not updating for a minute or two on "Fetching gem metadata from <a href="http://rubygems.org/" rel="nofollow">http://rubygems.org/</a>".</p>
  
  <p>I'm wondering how to prevent this in the future. Is there a reliable RubyGems mirror which I could specify as an additional source in Gemfile? And would it automatically switch over to the new source after a short timeout?</p>