[root@iZbp1he0bdge2g92l9fjnxZ ~]# systemctl  restart  zabbix-agent
Error getting authority: Error initializing authority: Error calling StartServiceByName for org.freedesktop.PolicyKit1: Timeout was reached (g-io-error-quark, 24)
Failed to restart zabbix-agent.service: Connection timed out
See system logs and 'systemctl status zabbix-agent.service' for details.

When installing the service using centos 7.4 an error was reported.

Error reported when starting zabbix.

Centos using Systemctl reports Error getting authority: Error initializing authority: Error calling StartServiceByName for org.freedesktop.PolicyKit1: Timeout was reached (g-io-error-quark, 24)

Error getting authority: Error initializing authority: Error calling StartServiceByName for org.freedesktop.PolicyKit1: Timeout was reached (g-io-error-quark, 24)

Solution:

ps -ef |grep polkit

Reinstall:
 pyum reinstall polkit

Restart
reboot