After upgrading environment to Symantec Endpoint Protection (SEP) 14.2, clients stop communicating with Symantec Endpoint Protection Manager (SEPM).
[2018-Oct-19 14:50:10.335770] [DEBUG] Received a HTTP_INTERNAL_ERROR response
[2018-Oct-19 14:50:10.335770] [INFO ] Heartbeat failed
SEP 14.2 with IPv6 disabled on clients.
The manager communication module Secars was not able to distinguish the source of requests sent from local host, Tomcat, or local SEP client.
This issue is fixed in Symantec Endpoint Protection 14.2 RU2. For information on how to obtain the latest build of Symantec Endpoint Protection, see Download the latest version of Symantec software here.
Enable IPv6 on the SEP clients and SEPM.