For some reason my previous post was marked as spam, so I don't know what will be acceptable.  I am building a small cluster of ten machines for testing.  Following this install guide   https://docs.cloudera.com/documentation/enterprise/6/6.2/topics/install_cm_server.html     [21/Jan/2021 09:20:10 +0000] 23992 MainThread agent ERROR Heartbeating to hdpen01.mydomain.com:7182 failed. Traceback (most recent call last): File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/cmf/agent.py", line 1396, in _send_heartbeat response = self.requestor.request('heartbeat', heartbeat_data) File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/avro/ipc.py", line 141, in request return self.issue_request(call_request, message_name, request_datum) File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/avro/ipc.py", line 254, in issue_request call_response = self.transceiver.transceive(call_request) File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/avro/ipc.py", line 483, in transceive result = self.read_framed_message() File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/avro/ipc.py", line 489, in read_framed_message framed_message = response_reader.read_framed_message() File "/opt/cloudera/cm-agent/lib/python2.7/site-packages/avro/ipc.py", line 417, in read_framed_message raise ConnectionClosedException("Reader read 0 bytes.")   I have a host file configured with all the names and IPs of the hosts pushed out to all the machines in the cluster.  I did enable auto-TLS, but if I have use_tls=1 I get the above with an additional SSLv3 error.  The cloudera manager machine is listening on 7182, and there is no firewall enabled.     ... View more