Question Setting up Pi-Hole as DNS on router breaks internet ?

[Ankursh287]

I've been facing disruption in my internet when I try to set Pi-hole as DNS on my router.

 

[MrN1ce9uy]

Changing DNS settings would disrupt your internet if not properly configured. Can you describe more of what IP and DNS settings you are using on both your Pi-hole and connected devices?

 

[bill001g]

A couple of assumptions that may not be correct. You have some device running pihole on your network and you have a different device running as your router. You are attempting to set the DNS in the router wan settings.

Most routers are pretty dumb they expect the DNS server to be on the internet. They will not forward DNS traffic to a server on your lan.

What you would need to do is either manually set the dns server in the nic setting on the end device or set the DNS in the DHCP configuration on the router to point to the pihole server. Not all router support setting the DNS in the DHCP settings.
Although even more complex you should be able to disable the dhcp server in the router and use the Pihole server to do the dhcp function being careful that it sends the router lan ip as the gateway.

 

[Ankursh287]

Changing DNS settings would disrupt your internet if not properly configured. Can you describe more of what IP and DNS settings you are using on both your Pi-hole and connected devices?

I've a 3 router network wherein 1st router is at Ground floor - modem/router provided by ISP at LAN IP 192.168.1.1 (WIFI disabled) and DHCP pool size set to 2, 2nd router is too at Ground floor (WIFI enabled) with WAN at 192.168.1.2, LAN IP 192.168.50.1 with DHCP enabled and DHCP pool size set to 200, lastly 3rd router is top floor (WIFI enabled) with WAN at 192.168.50.2, LAN IP 192.168.51.1 with DHCP enabled and and DHCP pool size set to 200.

Where shall I place my pi-hole (running on PiMox 7 on Raspberry Pi4), would be great if you can share your thoughts

 

[Ankursh287]

A couple of assumptions that may not be correct. You have some device running pihole on your network and you have a different device running as your router. You are attempting to set the DNS in the router wan settings.

Most routers are pretty dumb they expect the DNS server to be on the internet. They will not forward DNS traffic to a server on your lan.

What you would need to do is either manually set the dns server in the nic setting on the end device or set the DNS in the DHCP configuration on the router to point to the pihole server. Not all router support setting the DNS in the DHCP settings.
Although even more complex you should be able to disable the dhcp server in the router and use the Pihole server to do the dhcp function being careful that it sends the router lan ip as the gateway.

I've a 3 router network wherein 1st router is at Ground floor - modem/router provided by ISP at LAN IP 192.168.1.1 (WIFI disabled) and DHCP pool size set to 2, 2nd router is too at Ground floor (WIFI enabled) with WAN at 192.168.1.2, LAN IP 192.168.50.1 with DHCP enabled and DHCP pool size set to 200, lastly 3rd router is top floor (WIFI enabled) with WAN at 192.168.50.2, LAN IP 192.168.51.1 with DHCP enabled and and DHCP pool size set to 200.

Where shall I place my pi-hole (running on PiMox 7 on Raspberry Pi4), would be great if you can share your thoughts

 

[bill001g]

Why do you have so many routers. If it is purely for wifi you should be running the remote routers as AP instead so you have only 1 network.

Going to be messy to place the pihole device with 3 routers. Currently have have major issues with devices talking to each other that are connected to the different routers because of the NAT.

Best place would be on the 192.168.1.x network since everything can reach that. It would still be better to only have a single network.

 

[MrN1ce9uy]

As mentioned above, you are in a double (or in your case triple) NAT situation, meaning 2 or 3 routers are working independently, which is typically frowned upon for reasons that include network and connectivity issues. Use your wireless routers as AP (Access Points) that are all on the same LAN connected to your ISP's WAN. Your routers must have AP capability. Some do, some do not.

Then, you can more easily configure your DNS settings for your entire network.