$ bundle update
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Gem::RemoteFetcher::UnknownHostError: no such name (https://rubygems.org/gems/rake-10.2.2.gem)
An error occurred while installing rake (10.2.2), and Bundler cannot continue.
Make sure that `gem install rake -v '10.2.2'` succeeds before bundling.