I have had this error in the past due to port collision on the collector listening port, so I would suggest using netstat to verify no other process is listening on that port, and check the collector log for details.
Hi Dave and Babar,
I've attached collector log in this forum.
@Dave - this port is not assigned to any other process and only we have one collector per host.
It is suprising for me that the issue doesn't occur till i don't include this collector under collector host group.
it is working fine when it is act like an isolated collector.
The below information is in your collector's log.
2017-01-13 04:57:53 WARNING [Collector] Could not resolve FQDN for IP '10.50.230.99', using fallback 'DYNPRDEU07' as hostname. Had following exception: com.dynatrace.diagnostics.sdk.net.FqdnResolutionException: Cannot resolve FQDN for IP address '10.50.230.99'
2017-01-13 04:57:53 INFO [Collector] Could not resolve FQDN for 10.50.157.14
2017-01-13 04:57:53 WARNING [Collector] Could not open port 9998 on interface 'dynprdeu07' for collector communication! java.net.BindException: Cannot assign requested address
2017-01-13 04:57:54 WARNING [AgentListener] Specified binding address for Agent Listener not valid: dynprdeu07