Cannot connect to devices on my modems WiFi

[Nesto1000]

Hello all,

I have a bit of a weird issue that I can't seem to enter the correct terms in google for a fix, so please bare with me. Below is a bulletpoint list of my setup:

• I have Xfinity gigabit internet
• I bought a CM1000-1AZNAS modem that I cannot use. I am being forced to use Xfinity's modem because we have a wireless setop box.
• At the same time I bought a Nighthawk AC1750 to use as the router
• Since I cannot use the cable modem I bought and cannot disable the WiFi on the Xfinity modem, I have disabled the Nighthawk WiFi. (sad I know )
• Currently the Nighthawk is only acting as a "switch".
• All WiFi devices are connected to the Xfinity modem.

Now the problem is that I have is that I have multiple devices on the WiFi (printer, RokuTV, StreamLink) that need access to my computer for one reason or another. I consider myself pretty technical, but networking is something that I do not understand very well.

My end goal is to be able to see the wireless devices connected to my Xfinity modem on my computer that is hard wired to my Nighawk router. Any help is much appreciated.

Windows 10 - 1909

AC1750 - Firmware V1.0.4.84_10.0.58

Comcast Modem (2 ethernet port but can only use 1 for other reasons)

[plemans · Accepted solution]

If the xfinity device is in router mode and the nighthawk as well, you'll be in a double nat. This will cause the exact situation you're having. Easiest fix? place the nighthawk in AP mode. it turns over routing functions to the xfinity device. 

https://kb.netgear.com/30186/What-is-Double-NAT

Why can't you get the cm1000 working? 

[plemans · Accepted solution]

If the xfinity device is in router mode and the nighthawk as well, you'll be in a double nat. This will cause the exact situation you're having. Easiest fix? place the nighthawk in AP mode. it turns over routing functions to the xfinity device. 

https://kb.netgear.com/30186/What-is-Double-NAT

Why can't you get the cm1000 working? 

[Nesto1000]

So I was messing around with my router some more when my internet stopped working. I factory reset the Nighthawk this time and I belive that it put the nighthawk in AP mode when I went through the setup process. It did not go through a setup process last time. The only problem now is that I cannot access the Nighthwak console to disable the WiFi.

The reason that I cannot use the CM1000 is because I have an Xfinity wireless box for TV because the installer did not want to run wire to one particular room. Unfortuanetly only the Xfinity modem can stream to that box and I cannot do it fromt he Nighthwak. So I'm currently stuck with the modem rental.

[plemans]

A couple options. 

1. find the ip address that the netgear router is using through your xfinity's attached device list. use this to access the netgear router.

2. push the wifi on/off button on the netgear router for 2 seconds. 

Why not leave the wifi on and just make sure they're seperated enough to not interfere over wireless? It gives you extra coverage or backup wifi.

[Nesto1000]

Ah I didn't realize that there was an on/off button.

Doesn't it affect the signal strength in having two WiFi signals right next to each other?

[plemans]

Not if you seperate the wireless channels to prevent overlap. If you have them broadcasting on the same wifi channels then it does create interference.