Hi    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/dns_names.py", line 64, in collect result, stdout, stderr = self._subprocess_with_timeout(args, self._poll_timeout) File "/usr/lib/cmf/agent/src/cmf/monitor/host/dns_names.py", line 46, in _subprocess_with_timeout return subprocess_with_timeout(args, timeout) File "/usr/lib/cmf/agent/src/cmf/monitor/host/subprocess_timeout.py", line 40, in subprocess_with_timeout close_fds=True) File "/usr/lib/python2.7/subprocess.py", line 679, in __init__ errread, errwrite) File "/usr/lib/python2.7/subprocess.py", line 1249, in _execute_child raise child_exception   48487 Monitor-DataNodeMonitor throttling_logger ERROR Error fetching metrics at 'http://hdslave01.cibil.com:50075/jmx' Traceback (most recent call last): File "/usr/lib/cmf/agent/src/cmf/monitor/abstract_monitor.py", line 399, in collect_metrics_from_url openedUrl = self.urlopen(url, username=username, password=password) File "/usr/lib/cmf/agent/src/cmf/monitor/abstract_monitor.py", line 363, in urlopen password=password) File "/usr/lib/cmf/agent/src/cmf/url_util.py", line 58, in urlopen_with_timeout return opener.open(url, data, timeout) File "/usr/lib/python2.7/urllib2.py", line 406, in open response = meth(req, response)   File "/usr/lib/python2.7/urllib2.py", line 519, in http_response 'http', request, response, code, msg, hdrs) File "/usr/lib/python2.7/urllib2.py", line 444, in error return self._call_chain(*args) File "/usr/lib/python2.7/urllib2.py", line 378, in _call_chain result = func(*args) File "/usr/lib/python2.7/urllib2.py", 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    ... View more