mitchellh/vagrant — pull request #2254 by Caustic (2013-09-22 07:38:21+00:00)
Title: Fixed fqdn handling on debian/ubuntu

The issue was that the old method simply didn't work.
This is what I expect the hosts file to have in it:

127.0.1.1 new.fqdn.com new

This is what it was after set_hostname:

127.0.1.1 new.fqdn.com new old.example.com old

Or this if the user didn't set an fqdn in the Vagrantfile:

127.0.1.1 host host old.example.com old

This patch fixes that.