** Description changed:

- In Ubuntu 12.04, the way networkmanager now defaults to using dnsmasq as
- a local resolver seems to break many VM configuration using VirtualBox,
- because VirtualBox's DHCP server tries to inherit the host's DNS
- configuration and provide it to the guest. In the default configuration,
- the only DNS server visible to applications is the dnsmasq server, which
- is accessable only from localhost.
+ In Ubuntu 12.04, the way NetworkManager defaults to using dnsmasq as a
+ local forwarding resolver breaks VM configuration using VirtualBox.
  
- The end result is that a virtual machine that configures networking via
- DHCP will inherit no working DNS servers, resulting in reconfigured DNS
- in the guest.
+ In 12.04, VirtualBox's DHCP server provides the host's resolver's list
+ of nameserver address to the guest. When the host's resolver is
+ configured to communicate with a local nameserver via a loopback
+ address, the guest will receive loopback IP addresses as nameserver
+ addresses; but this does not work because there is no nameserver running
+ on the guest. The guest's resolver should be configured to use the
+ nameserver running on the *host*.
  
  [Impact]
  DNS doesn't work in guests
  - when it uses the DNS server from the DHCP response and
- - the host uses networkmanager
+ - the host uses NetworkManager
  
  [Test Case]
  Running "host ubuntu.com" on the command line fails.
  
  [Development Fix]
  Fixed during Raring cycle.
  
  [Stable Fix]
  Is being fixed in 4.1.12-dfsg-2ubuntu0.3 upload to precise-proposed and
  4.1.18-dfsg-1ubuntu1.2 upload to quantal-proposed.
  
  [Regression Potential]
  We should verify that DNS in guests still works when the host
  doesn't use networkmanager.

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https://bugs.launchpad.net/bugs/1031217

Title:
  Ubuntu 12.04's use of networkmanager+dnsmasq breaks DNS for virtualbox
  VMs

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