Steps to reproduce:

1. I was include hosts by webapge and the server stopped working.
2. I have already restarted the server and the service reporting the following error:

   # systemctl status zabbix-server
   ● zabbix-server.service - Zabbix Server
    Loaded: loaded (/lib/systemd/system/zabbix-server.service; enabled)
    Active: activating (auto-restart) (Result: exit-code) since Qui 2018-05-03 18:23:23 -03; 1s ago
    Process: 1176 ExecStart=/usr/sbin/zabbix_server -c $CONFFILE (code=exited, status=1/FAILURE)
   
   Mai 03 18:23:23 Grifo systemd[1]: zabbix-server.service: control process exited, code=exited status=1
   Mai 03 18:23:23 Grifo systemd[1]: Failed to start Zabbix Server.
   Mai 03 18:23:23 Grifo systemd[1]: Unit zabbix-server.service entered failed state.