Hi Subru Krishnan, I've taken a look at TestAMRMProxy. There is a relevant test testE2ETokenRenewal. However, this test is really testing that AM can receive the new AMRMToken when AMRMProxy rolls its master key.
Here in this Jira, the problem is between RM and AMRMProxy, when RM issues a new token,AMRMProxy should intercept it without forwarding it to AM. It is non-trivial to add it into TestAMRMProxy because both AMRMProxy and RM share the same config for rolling interval.
I added tests in TestAMRMProxyService to cover this case. I also modified the test name and comments in TestAMRMProxy for clarification. Please see v3.patch