UnicastBackwardsCompatibilityIT fails frequently on 2.1 Windows

[cbuescher]

This test fails quiet frequently over the last few days on 2.1 branch, going through the failure mails it seems its only on Windows 2012 machine. Last seen was

http://build-us-00.elastic.co/job/es_core_21_window-2012/129/

and the top of the stacktrace reads like

java.lang.IllegalStateException: Failed to start elasticserch. Responses: [couldn't find elasticsearch bound to localhost:29301!]
    at __randomizedtesting.SeedInfo.seed([24181440F4C4423C]:0)
    at org.elasticsearch.test.ExternalNodeServiceClient.interact(ExternalNodeServiceClient.java:85)
    at org.elasticsearch.test.ExternalNodeServiceClient.stop(ExternalNodeServiceClient.java:60)
    at org.elasticsearch.test.ExternalNode.stop(ExternalNode.java:231)
    at org.elasticsearch.test.ExternalNode.close(ExternalNode.java:257)
    at org.apache.lucene.util.IOUtils.close(IOUtils.java:97)
    at org.apache.lucene.util.IOUtils.close(IOUtils.java:84)
    at org.elasticsearch.test.CompositeTestCluster.close(CompositeTestCluster.java:266)
    at org.apache.lucene.util.IOUtils.close(IOUtils.java:97)
    at org.elasticsearch.test.ESIntegTestCase.clearClusters(ESIntegTestCase.java:588)
    at org.elasticsearch.test.ESIntegTestCase.afterClass(ESIntegTestCase.java:1978)

Going throught the output it is not clear to me if this is a follow up error cause by something else.

[nik9000]

If I had to guess blindly I'd guess that I left a bug in ExternalNode that let it try to shut down the node twice. Why it only comes up on windows is a mystery to me though.

[clintongormley]

Old test failure. Closing