Router Login IP vs Router IP

I have my GL-AX1800 plugged in to my ISP-provided gateway/router (NL 3120). ETH1 on NL3120 to WAN on GL-AX1800 with WiFi turned off.

I don't want my ISP gateway/router (required for modem) getting in the way/handling anything more than necessary.

I assumed that moving my GL-AX1800 to DMZ is easiest, but wanted to confirm if that is the best route. If so, I would move the address of the router shown under "Ethernet":

Thanks in advance.

I think the best way would be setup the ISP modem to bridge mode.

But some other settings would be checked firstly.

  1. Make sure the ISP modem is not a customized one with some settings as tr069, otherwise you cannot set it as bridge.
  2. If the Internet connection is dynamic IP, just set it as bridge, then plug and reply.
  3. If the Internet connection is PPPoE, then write down the usernmae and password, vlan ID if required, copy them to the Internet settings of AX1800, then check it works or not.

It's PPPoE and TR-069.

Is it not possible to set as bridge?

The TR-069 client menu has:
Checkbox with "ENABLE TR-069" (Checked)
OUI- serial: MAC or Serialnumber
WAN INTERFACE USED BY TR-069 Client and "Any_WAN" selected.
Checkbox with "Connection Request Authentication" (checked)
Connection REquest user name
Connection Request Password
Connection Request URL
Checkbox with Enable STUN Client (unchecked)

Yes, you cannot set the ISP modem router as bridge mode in your case.
And you cannot remove it, otherwise you shall not have the Internet access.

Just connect as: Internet --- NL3120 (LAN port) --- (WAN port) AX1800 (LAN port or WiFi) --- other devices.
Make sure the two subnet are different.
And if some remote access applictions is requires, set port forwarding or DMZ on NL3120, such as VPN server.
Other features, such as VPN client shall work fine, no need for other settings.

Oh man that sucks. How big of a drawback is this, being forced to go DMZ vs using Bridge mode with a PPPoE DSL connection? I wonder if I can inquire with my ISP about any potential work-arounds...? Or is that just not possible based on the type of connection/infrastructure they're using?