Installation failed. Failed to receive heartbeat from agent.

[#1]

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.

[#2]

@NegativeNathan There might be some issue with Auto-TLS where the deployment interrupted and  you are getting this error. 

I would suggest you to check if Auto-TLS is enabled successfully and then restart CM server again and then restart management services to get Auto-TLS in effect. 

[#3]

@GangWarAh, well it appears that the certificate store is in place on the server.  I tried to disable TLS for agents, but it reverts on cloudera-server restart. 

[#4]

@NegativeNathan Have you disabled this from CM or agent configuration file?