TP-Link, can't set LAN IP as DNS IP, DNS IP defaults to ISP's DNS [PIHOLE AS DHCP]

[LavanderLover]

Hi, all, new here.

I'm also absolutely new to Pi and router configuration, so yeah. I've read trough the issues, I understand that you can't set an internal IP as DNS on a TP-Link (Deco App won't work as I have an Archie C6, I tried). So, I turned on the DHCP option in the PiHole, and clients do connect to the PiHole, but ads are not blocked. Query Log says it blocks Microslop telemetry, so it's good at least for something. I use this list - https://media.githubusercontent.com/media/zachlagden/Pi-hole-Optimized-Blocklists/main/lists/all_domains.txt (and a couple more, but they overlap as I understand)

I guess the problem is that under router's "Advanced Settings" Network->Internet Primary and Secondary DNS are preset to our IPS's DNS Servers, which is changeable, BUT NOT TO THE PIHOLE ADDRESS or to 0.0.0.0 . I guess I cloud use an adblocking DNS, but it's not sure if it wont bleed through too.

Also tried blocking domain "purple.com" in the web interface, as a test. Clients connected to the PiHole DHCP still have access and connect the website. Dunno what to make of this

I have to leave tomorrow morning, while writing this it turned into "today", so it's unlikely that I'll have an opportunity to bother with this problem this or even next week.

I also got an idea (bad one) to bypass the limitation on my router: connecting my Pi 2 to a different network should solve the problem. Thus leaving it connected via cable somewhere or connecting to a public wifi. It's not a good idea, but imagining myself sneaking to the router of a library, which is 300km, away from where I live, JUST to leave beside it a """selfhosted"" 24/7 server is entertaining.

I'm very open to suggestions how to resolve my issue.

Expected Behaviour:

Block sites from blocklists, blocklisted domains and other unwanted connections.

Actual Behaviour:

Ads and websites pass through blocklists, but Microsoft telemetry is blocked.

Debug Token:

htpps://tricodder.pi-hole.net/sg7UDEv3/

[Bucking_Horn]

@LavanderLover

I've read trough the issues, I understand that you can't set an internal IP as DNS on a TP-Link

This looks similar to older issues with TP-Link routers, see e.g.

Can't setup network-wide DNS because of router

This behaviour would be common for some TP-Link routers, which do not allow to set their upstream DNS server to an IP address within the router's own subnet range. The solution as proposed by TP-Link personnel is to avoid configuring the router's upstream DNS servers, and change just the DNS server via the router's DHCP settings: [tp-link-router-range-shift]

[LavanderLover]

I have tried that too, no clients would connect, but I'll try again once I'm back.

[Bucking_Horn]

Clients would only start to use the new DNS server upon renewing an existing or acquiring a new DHCP lease from your router.
You may force a client to do so e.g. by dis- and reconnecting its wifi, or by power cycling it.

[rdwebdesign]

@LavanderLover

I guess the problem is that under router's "Advanced Settings" Network->Internet

I think you are trying to modify the wrong DNS server option.

Do not change the "Internet" DNS server (keep using the original ISP server, or Google, or any other public DNS server).

Go to Advanced settings, open the Network > DHCP Server page.

Then set Pi-hole as both DNS servers:

Important: If you set this option, you need to disable Pi-hole DHCP server and enable the router DHCP server.

Note:

Your router may show different pages/options in the web interface.

I used the TP-Link emulator for Archer C6 as a reference, but you need to find the correct option in your own router interface.

[LavanderLover]

Update: I still should have a very ozyxel router stashed somewhere, cloud try things out with that one.

[LavanderLover]

Didn't know that. I still got two hours before I leave, so I'll try now.

[LavanderLover]

Clients connect! And it appears to work! Thank you!

[LavanderLover]

Thank you!