Adding node fails "Join completion call failed"

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4.0.0-2134

Today's build

Failed to add node 172.23.105.62:8091 to cluster. Join completion call failed. Got HTTP status 500 from REST call post to http://172.23.105.62:8091/completeJoin. Body was: "[\"Unexpected server error, request logged.\"]" ns_cluster005 ns_1@172.23.105.54 13:19:01 - Thu May 14, 2015
Add transaction of 'ns_1@172.23.105.62' failed because of {error,
complete_join,
<<"Join completion call failed. Got HTTP status 500 from REST call post to http://172.23.105.62:8091/completeJoin. Body was: \"\\\"Unexpected server error, request logged.\\\"\"">>,
{error,rest_error,
<<"Got HTTP status 500 from REST call post to http://172.23.105.62:8091/completeJoin. Body was: \"\\\"Unexpected server error, request logged.\\\"\"">>,

}} ns_cluster000 ns_1@172.23.105.54 13:19:01 - Thu May 14, 2015

All automation tests fail in setup phase, hence marking as test-blocker:

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ERROR: swap_rebalance_replication_with_view_queries_and_ops (xdcr.rebalanceXDCR.Rebalance)
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Traceback (most recent call last):
File "pytests/xdcr/rebalanceXDCR.py", line 9, in setUp
super(Rebalance, self).setUp()
File "pytests/xdcr/xdcrnewbasetests.py", line 2246, in setUp
self.__setup_for_test()
File "pytests/xdcr/xdcrnewbasetests.py", line 2332, in __setup_for_test
self.__init_clusters()
File "pytests/xdcr/xdcrnewbasetests.py", line 2433, in __init_clusters
cluster.init_cluster(disabled_consistent_view)
File "pytests/xdcr/xdcrnewbasetests.py", line 978, in init_cluster
use_hostnames=self.__use_hostname).result()
File "lib/tasks/future.py", line 160, in result
return self.__get_result()
File "lib/tasks/future.py", line 112, in __get_result
raise self._exception
AddNodeException: Error adding node: 10.3.4.187 to the cluster:10.3.4.186 - ["Join completion call failed. Got HTTP status 500 from REST call post to http://10.3.4.187:8091/completeJoin. Body was: \"\\\"Unexpected server error, request logged.\\\"\""]

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