Xr1000 V2 having DNS issues and unable to connect to websites

I see you already have a gateway router with the ISP. Your ISP Modem already has a built in router and wifi. This would be a double NAT (two router) condition which isn't recommended. This would be a double NAT condition which isn't recommended. https://kb.netgear.com/30186/What-is-Double-NAT
https://kb.netgear.com/30187/How-to-fix-issues-with-Double-NAT
Couple of options,
1. Configure the modem for transparent bridge or modem only mode. Then use the NG router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ/ExposedHost or IP Pass-Through for the IP address the NG router gets from the modem. https://kb.netgear.com/25891/DMZ-on-NETGEAR-routers
https://kb.netgear.com/24086/How-do-I-set-up-a-default-DMZ-server-on-my-Nighthawk-router
3. Or disable all wifi radios on the modem and connect the NG router to the modem, LAN to LAN configure AP mode on the NG router.
https://kb.netgear.com/20927/How-do-I-change-my-NETGEAR-router-to-AP-mode
https://community.netgear.com/t5/Orbi-WIFI-6-AX-AND-Wi-Fi-6E-AXE/Procedure-for-Factory-reset-of-RBS850/m-p/2367505/highlight/true#M53985
Try option #2 first...

Another test to try to see if the XR router handles differently would be to configure the XR router for AP mode whlie you using the ISP gateway as a router with it's wifi disable and test for DNS issues.

Remove any other 2ndary routers from the mix as well while testing. 

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robturpin wrote:

By the way, while I've got some knowledgable folks available, what's the best/proper order to connect the following for both network effeciency and to prevent issues like flooding and loops, etc.?

 

1. Cable Modem: Xfinity XB8 with 4 gigabit ethernet ports

2. Main Router: either NetGear XR1000v2 or the TP-Link Archer C7 AC1750

3. Main Switch: NetGear GS108 8-port unmanaged switch

4. Second Switch: Generic 5-port unmanaged switch

5. Second Router: Archer AX1800

 

The reason for two routers is because we have extended family staying in an outbuilding (which is hardwired via a single outdoor rated CAT8 130' cable) and they have their own private network (running through my main router and assigned an IP from it), and the second switch is to "split" that CAT8 feed line to their router and my external NetGear ReadyNAS Ultra.

 

Thanks for your wisdom!

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