DataNode appears to require DNS name resolution as opposed to direct ip mapping

DataNode appears to require DNS resolution of nodes via the class org.apache.hadoop.net.DNS as opposed being able to use a specified ip.

as an example, i was not able to set up more then one instance of dfs datanodes on one box using loopback w/ varying ports since DataNode
resolved the ip of 127.0.0.1 to be "foo.bar" which was then mapped to the dhcp allocated ip of 192.168.0.***, which was not addressable by the
rest of the dfs cluster (namely namenode).

while this example is trivial one should be able to use the very same process yet change only the ip's of the nodes and have things work as
expected.

it would be nice to not always require nds resolution.