Where are the default iptables stored ?

[Denna]

If you install the Asuswrt-Merlin firmware, wiping out any previous configuration, where are the default iptables rules stored ?

Is there any configuration in the WebGUI that will add/modify/delete iptables rules ?

 

[RMerlin]

There are no "default rules", everything is configured by the firmware code.

 

[sfx2000]

Is there any configuration in the WebGUI that will add/modify/delete iptables rules ?

They're in the firmware, but those are in the realm of the 3rd rail - touch them in the firmware, and you'll die.

There is a mechanism to extend them via scripts - there's plenty of posts/threads on how to do this...