The test failures are unrelated (job history and capacity scheduler, both mapred whereas this only touches hdfs)
While I think the discussion above is valuable, since this blocks
HADOOP-5888 I'd like for this to be committed and we can continue work on making image transfer more sane in another JIRA.
As for switching to POST rather than the "GET with a callback to another GET", I looked into this today and, while easy, I'm not sure it's a great idea. I think there are some people who are relying on the GetImageServlet on the 2NN for backup purposes, so removing the Jetty from the 2NN would break that.