trying to view library on TV on same network using both a xfinity router and netgear router

Hey. I am renting an apartment from someone that lets me use their xfinity internet. Their setup uses the xfinity modem/router connected to a netgear wireless router, that then I connect my mac laptop to. I cannot connect to my Plex Media Server on my TV on the same network. MY phone also can’t connect to my mac using the wifi using a mac app called reflector. So something is blocking me.
From what I have read, I am probably experiencing a double NAT issue. When I take the troubleshooting test, I show the double NAT symptoms. I am able to login to the xfinity router page and see in the troubleshooting instructions that forwarding a port might be a viable option for me. I want to change things as minimally as possible as its not my setup. The instructions say to use port 32400 and my netgear routers IP address… How do I find that? Then what setting do I have to change within plex media servers settings?
should I check the “Manually specify public port” box and use 32400 within the server ----> remote access area? Or does this section even matter since my problem is across my local network?
Under server ------> network should “Enable server support for IPv6” be checked?
Any suggestions or related experience would be awesome. I wish there was something I could turn off to allow all of my devices to easily communicate with each other but I guess port forwarding for each issue is my next best choice. I can’t figure out what xfinity’s port forwarding setup want as the IP address. I think it should be the netgear router’s IP but I have no idea what that is!

Let’s take a step back - why do you need to have two routers? I understand the first, that perhaps the xfinity is “locked” or such, but the second - can’t you just turn off DHCP and make it a dumb switch?

Hi Peter. Thanks for the response. I’m not sure if I can turn the netgear router into a switch. But I do want to avoid making any drastic maneuvers. I want to try an make this work work without consulting the family that owns the routers. Their system is elaborate enough that I feel making any significant change would disrupt their internet use. All of the ports in both routers are being used. There’s also a large Sonos system set up. So ideally I’d like to make as small of a change as possible. For instance, troubleshooting on this site says to either put first, xfinity router in “bridge” mode. I’m of course not seeing this option within xfinity’s dashobard but I could go along these lines… or another option expressed is to port forward 32400 and input and input my netgear router’s IP. THIS would be the option I’d favor. I have no idea what the netgear"s IP is though or how to find it… Would it be something like 192.168… or 10.0.0.1? Those are the IPs I’m seeing and xfinity’s port forwarding only seems to like the 10.0.0… etc IP. Any further help would be awesome. I can’t afford to rent a movie again tonight!! haha

any ideas?!

Sorry for not getting back to you. I could’ve sworn that I’d replied in this thread but alas, sadly not. My bad.

Well, the “bridge mode” you ref to is exactly what I implied in my first answer. If you turn off the DHCP (or bridge it) it will just act as a switch (simplified). Best option is to either do that on the xfinity (but as you’ve discovered, many companies takes it option out. Sometimes one can call them and ask for it.) or the netgear router. Having two routers just makes everything so much more difficult.

It’s hard for me to give you exact hints since I’m not from the US of A and not seen this xfinity router/modem, but I’ll give it a go. On the xfinity router you should have a list of connected devices, it might be called a DHCP lease list or just, well, connected devices I assume. There you should be able to see which IP the Netgear router has been assigned and you could potentially browse to it. Another option is to disconnect the cable running between the two of them and connecting one cable directly in to the Netgear router and set a static IP on it within the DHCP range that the xfinity want’s to set it all. You might also be able to pertain it by going to CMD (on a windows computer that is directly connected to the Netgear router) and type in “ipconfig” and use the Gateway IP to reach the Netgear router.

My best recommendation, if you can’t make either router ‘dumb’ is to make sure that all devices that should talk to eachother locally on the same LAN, is connected to the same router. Don’t connect them across both. And make sure that the netgear router get’s it’s own DHCP range. If the xfinity hands out 192.168.1.X IP’s, your Netgear should hand out 10.X.X.X (or vice versa).