@Somnus Thank you, this answer makes sense to me. I've been at it for days and could not find a way to do this. Not happy with ER605 at all now :( But I guess it's on me. Should have bought a more...

@HelsingL This would not work with the modem I am using. It has an option to use a cascaded router for distributing public IPs. But it forwards all traffic for that public subnet to the router, using...

I have a public IP block (/26) assigned to me by my ISP (AT&T). The modem is setup to forward all traffic to this block to the cascaded router (ER605). However, I can't figure out how to setup the...