My ISP has installed a modem/router (D-Link DIR-825) on the ground floor of my house where the internet is set up. I recently purchased a Netgear Nighthawk XR500 Pro Gaming Router and set it up upstairs and connected it via ethernet cable to the modem downstairs. Everything works fine, except I get Double NAT issues on Xbox and I'm sure this also effects the performance of other devices.
After doing some research, I was able to find out that I need to put my first modem/router into "Bridge Mode". However, the first modem/router does not support "Bridge Mode". I've heard of solutions related to DMZ, Port Forwarding, and disabling DHCP servers as well.
What I tried:
As suggested by @Netduma_Alex, I found out my XR500 router's WAN IP and placed the IP in the DMZ settings in the Modem/Router Upstream. This fixed the problem temporarily and my NAT status was OPEN. A few hours later, I checked the Network settings on Xbox and it was back to "Double NAT". I checked the DMZ settings again and everything was fine. I even ensured that the router has a fixed/reserved IP which it does.
What can I do?
Am I doing something wrong? Do I need to disable DHCP for the first modem/router even though my DMZ settings are correct? I'm really running out of options here and I'm willing to buy a new modem/router as the first modem/router.
Next Steps:
If there is nothing else I can do, I do not mind purchasing another modem/router to function simply as a bridge. If I am purchasing a new modem/router to function as a bridge, which Netgear model do you suggest will work best with the XR500? Also which Netgear Modem/Routers support Bridge mode?
Re: Follow Up: How to use the XR500 as a second router? How do I avoid double NAT?
Best way to ensure compatibilty with your ISP is to obtain a list of modems from the ISP that will work with their system (DOCSIS 3.1 is the current standard for cable modems but DOCSIS 4.0 if you have 10 Gbits/s) then do further research on that list to ensure they can be put in bridge mode. If you purchase your own modem it should save money on your cable bill as well. Once you have decided on the modem you want that is compatible with your ISP post it here before you purchase-there are a lot of experts on this board that have experience with countless cable modems eager to help.
