firewalld not listing any active zones?
When running
[root@host ~]# firewall-cmd --get-active-zones
[root@host ~]#
[root@host ~]# firewall-cmd --get-default-zone
public
I am not getting any active zones. How can I activate a zone?
You activate a zone by binding a network interface or source IP address range(s) to it. Any firewall rules in the zone then apply to that network interface or IP address range(s).
On a similar case, I took a peek with strace and realized, that FirewallD had somehow lost D-Bus access completely.
The easiest fix was to reboot the Linux. That helped and FirewallD saw active zones again.