Automatic NAT Rules Generation

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pfSense and Automatic NAT Rules Generation

In a default single WAN connection configuration, pfSense automatically generates NAT rules for every directly connected interface, and any networks reachable on internal networks you define via static routes, to NAT outbound traffic to the Internet to the WAN IP.

In a default multi-WAN configuration, pfSense automatically generates NAT rules to NAT any internal subnet leaving any interface with a gateway (including OPT WAN connections).

With Advanced Outbound NAT (AON), you can disable this automatic rule generation and define your own outbound NAT rules manually.