Zabbix server SELinux policy
I finally figured it out. Zabbix Server has an SELinux bool to allow httpd to communicate with port 10051. To set it, issue the command sudo setsebool httpd_can_connect_zabbix 1.
This will allow web interface to show if the Zabbix Server is enabled or not without having to disable SELinux!
No answer gave proper advice on how to update the SELinux rule as well as making the settings persist upon a server reboot, to do so do the following:
# setsebool -P httpd_can_network_connect on # setsebool -P httpd_can_network_connect=true
This was done on RHEL7.