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The Cloudera Manager Agent is not able to communicate with this role's web server.

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I am getting  "The Cloudera Manager Agent is not able to communicate with this role's web server." error in HDFS, HBASE and YARN services,

rest services are not giving any error.


I am able to execute the code in all services but still getting above error message.  


Following are the logs in "cloudera-scm-agent.log" :


ERROR Failed to collect java-based DNS names
Traceback (most recent call last):
File "/usr/lib/cmf/agent/src/cmf/monitor/host/", line 64, in collect
result, stdout, stderr = self._subprocess_with_timeout(args, self._poll_timeout)
File "/usr/lib/cmf/agent/src/cmf/monitor/host/", line 46, in _subprocess_with_timeout
return subprocess_with_timeout(args, timeout)
File "/usr/lib/cmf/agent/src/cmf/monitor/host/", line 40, in subprocess_with_timeout
File "/usr/lib/python2.7/", line 679, in __init__
errread, errwrite)
File "/usr/lib/python2.7/", line 1249, in _execute_child
raise child_exception


48487 Monitor-DataNodeMonitor throttling_logger ERROR Error fetching metrics at ''
Traceback (most recent call last):
File "/usr/lib/cmf/agent/src/cmf/monitor/", line 399, in collect_metrics_from_url
openedUrl = self.urlopen(url, username=username, password=password)
File "/usr/lib/cmf/agent/src/cmf/monitor/", line 363, in urlopen
File "/usr/lib/cmf/agent/src/cmf/", line 58, in urlopen_with_timeout
return, data, timeout)
File "/usr/lib/python2.7/", line 406, in open
response = meth(req, response)


File "/usr/lib/python2.7/", line 519, in http_response
'http', request, response, code, msg, hdrs)
File "/usr/lib/python2.7/", line 444, in error
return self._call_chain(*args)
File "/usr/lib/python2.7/", line 378, in _call_chain
result = func(*args)
File "/usr/lib/python2.7/", line 527, in http_error_default
raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
HTTPError: HTTP Error 503: Service Unavailable


Correct me if i am wrong, is these error are related to HTTPs server?

I didn't get these error in CDH4.5, after installation fresh copy of CDH5.2 I am getting these error.

Does HBase,HDFS,YARN services requires mandate HTTPS server or TLS configuration, if so how to fix the configuration ?


Thanks in advance   

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