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README
UniFi Firewall
Modern UniFi Network replaced the old LAN-IN / LAN-LOCAL / WAN-IN rule groups with a zone-based firewall. Every network belongs to a zone, and policies govern traffic between zone pairs rather than between interfaces. This is a better model and a worse migration, because the old API endpoint still exists and still answers.
Why your firewall rules look empty
udm raw GET /proxy/network/api/s/default/rest/firewallrule
# []
An empty array. The endpoint is alive, authenticated, and lying by omission: on a zone-based controller your rules are not there. They are here:
udm policies # GET /proxy/network/v2/api/site/default/firewall-policies
udm zones # GET /proxy/network/v2/api/site/default/firewall/zone
This is the opening of the README. Read the full README on GitHub.