I have the Tmobile nok 5g21 gateway. I have an ASUS RT AC5300 running DDWRT with Open VPN configured with 3wifi bands . The VPN is configured to work based on static IP and routing for only 4 devices with a kill switch for those 4 - so if the VPN goes down they lose internet. Everything else uses the nonVPN connection.
I unplugged my existing modem from Spectrum and plugged it into the Tmobile gateway. It didn’t “just work” so my question is how do I get it to work. Looking for someone who has done this with this router or a similar one and can provide detailed instructions. Or links to such instructions. Not looking for a reply like “turn it into an access point” or some I’ve seen about NAT or double NAT or whatever.
I expect that you cannot turn the tmobile gateway into just a modem and get routing from my ASUS and that some kind of configuration is going to be needed on the my ASUS side.
I expect tmobile tech support is going to be useless in helping me configure this so thank anyone who replies in advance!