I don't know of a specific document speaking to this, but this doc i think describes it right. https://securitynetworkinglinux.wordpress.com/2019/04/19/how-create-a-site-t... in section 2.3 is where you change My Identifer to be the natted non RFC1918 ip that the right side will see. On 2/10/2022 1:55 PM, William Herrin wrote:

On Thu, Feb 10, 2022 at 10:47 AM Juri Grabowski <nanog@jugra.de> wrote:

...

Or buy official supported hardware from https://shop.opnsense.com/ Howdy,

Opnsense looks like it might work. I dug through some of the documentation but didn't find something entirely on point for my use case. Are you aware of any documentation which describes:

LAN - OPNSense Appliance - (rfc1918) NAT Appliance (dynamic IP) - Internet - (static IP) OPNSense appliance - LAN

Where the left-side OPNSense is responsible for establishing and keeping the NAT translations alive without any special configuration on the NAT?

Thanks, Bill