I see a lot of questions about the error "Zabbix server is not running" from users. 

This indicates a loss of connectivity between the frontend and the server (there're too many reasons: wrong ip/port, selinux, firewall).

You can check if it's running or not by doing "ps aux" on the server when the Zabbix server is running.

So please change the message to something like "Zabbix frontend couldn't connect to Zabbix server IP:PORT" + add the link to the documentation how to debug and fix such error.

Thanks.