Syslog and filebeat assistance request

We have been running ELK v. 6.2.x
We have a central syslog server on EL5 pushing log files with filebeat to logstash
I have been tasked with setting up a new central syslog server on EL7 (replace EL5 instance).
Filebeat-6.2.2 is the current version on the EL5 host, matched filebeat version on EL7 host.

when testing the output its all ok.
parse host... OK
dns lookup... OK
dial up... OK
talk to server... OK

What I am not getting are the latest syslog details displaying in Kibana.

Please tell me how I can verify the syslog data is getting to Logstash? Elasticsearch?

Any advice would be much appreciated. TYIA!

Please let me know if there are details you want to know about the environment.
Sorry, I am an elk-noob.