Firewalld without interfaces on public zone

Question

On my Oracle Cloud server, the public zone has no interfaces attached, neither does any of the other zones.

But still if I allow a port in the public zone, it does allow the traffic through.

So why is it not needed to add the adaptor (eth0 or enp0s1) to that zone?

Answer 1

Probably because the public zone is set as the default zone. You can check that with firewall-cmd --get-default-zone

https://firewalld.org/documentation/zone/default-zone.html