Per Device DNS Setting

[ronmis]

My Setup is as follows : Asus RT-AX3000 running the latest Merlin firmware. I have Frontier internet and as their DNS is unstable I am using Google's DNS 8.8.8.8, 8.8.4.4 (LAN - DHCP Server tab - DNS and Wins Server Setting)

I also have a pihole (DNS Server with adblocking features https://pi-hole.net/) with static address 192.168.1.175

I only want my iphone to use the DNS, so in my iPhone's wifi settings, I set the DNS manually to 192.168.1.175 and all's working well.

I'm wondering if I can do the same at the router level. My iPhone has a static IP address and I see a DNS Server (Optional) column (LAN - DHCP Server tab - Manually Assigned IP section), but setting that to 192.168.1.175 doesn't do anything.

 

[dave14305]

Is the iPhone IP configured as a Manual IP in the WiFi settings? It would all have to be Automatic on the phone to get the reserved IP and DNS from the router DHCP settings.

 

[bbunge]

Sure, you can assign a specific DNS server using a manually assigned IP address.

But, you may be better off setting the DNS Server 1 and 2 in WAN. That way the router will use those DNS servers and the rest of your clients can use the router for DNS. Better yet set up DoT and DNSSEC in WAN to encrypt and verify DNS queries. Enable DNS Filtering to Router in LAN/DNS FIlter for added security. Then add the Pi-Hole IP address to LAN/DHCP Server/DNS Server 1 and leave DNS Server 2 blank so clients can fall back to the router if the Pi-Hole goes wonky.

Edit: Cloudflare Security (1.1.1.2, 1.0.0.2) is safer to use than Google

 

[ronmis]

Thanks guys, I tried the DNS Server (Optional) for my iPhone and it worked this time. Hope it stays that way.

@bbunge, I used to use Cloudflare Security, but my Weather Station stopped transmitting data so i switched to Google's DNS.

 

[ColinTaylor]

As @bbunge mentioned you would be better off specifying 8.8.8.8 and 8.8.4.4 as your WAN DNS and leaving the LAN DNS fields empty. Otherwise you're not benefiting for the router's DNS caching and local name resolution.

 

[ronmis]

Thanks @ColinTaylor I changed the WAN DNS to 8.8.8.8 and 8.8.4.4 and left the LAN DNS empty.

Went through this old thread to understand the benefits - https://www.snbforums.com/threads/what-does-wan-dns-setting-do.48227/

 

[cptnoblivious]

Glad that's working.

FYI, another way to configure it is to have the clients point to pihole and pihole point to your router as the upstream DNS.

 

[ronmis]

@cptnoblivious Thank you.

I want to avoid too many points of failure, in your method, if pihole went down, my whole network would go down too. And I need adblocking only on my iPhone and a bunch of other devices, so I set their dns server to the pihole manually.