TestNMProxy unit test is failing

[INFO] Running org.apache.hadoop.yarn.server.nodemanager.containermanager.TestNMProxy
[ERROR] Tests run: 3, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 4.806 s <<< FAILURE! - in org.apache.hadoop.yarn.server.nodemanager.containermanager.TestNMProxy
[ERROR] testNMProxyRPCRetry(org.apache.hadoop.yarn.server.nodemanager.containermanager.TestNMProxy)  Time elapsed: 1.188 s  <<< FAILURE!
java.lang.AssertionError
	at org.junit.Assert.fail(Assert.java:86)
	at org.junit.Assert.assertTrue(Assert.java:41)
	at org.junit.Assert.assertTrue(Assert.java:52)
	at org.apache.hadoop.yarn.server.nodemanager.containermanager.TestNMProxy.testNMProxyRPCRetry(TestNMProxy.java:171)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.internal.runners.statements.FailOnTimeout$StatementThread.run(FailOnTimeout.java:74)