How to set a self-hosted DNS server for a Wifi network and "DNS private mode"?

packoman

I want to set the DNS server configuration, so that it uses my AdGuard Home instance (also accessible externally through Wireguard VPN).

I tried this both through the Wifi settings and DNS private mode. In both cases the "Save" button (at the bottom right) is disabled, so I cannot configure it. I tested this from the "Owner" profile.

Is there any permission that I need to set for this?

Here is what I have tried (from my local network)...

For the Wifi I do:

navigate: Settings > Network & internet > Internet > Click on cog-wheel of my Wifi network > Click on Pen in top-right corner
Select drop-down in "Advanced options" and click "DHCP"
Select "Static"
Set DNS1 and DNS2 to IP address of my DNS server (it has two IPs for Ethernet and Wifi)
Result: "Save" at bottom right is greyed out. It is greyed out, even if I do not modify the DNS settings.

For Private DNS mode:

navigate: Settings > Network & internet > Private DNS
select: "Private DNS provider hostname" (this causes the "Save" button to become disabled)
enter IP of my AdGuard instance in field below (Title: "Enter hostname of DNS provider").
Result: "Save" at bottom right remains greyed out.

trilogy6202

packoman

As @DeletedUser87 said "Private DNS" probably isn't what you want for lan DNS as it involves setting up a local certificate authority and signed TLS certificates.

If you wish to solve this with a static IP on your phone, you have to fill in the IP and field with an unused IP from the static range on your subnet. And fill in the IP of your gateway (router) if it's not ....1 on the local subnet.

A better approach however, would be to configure your router to advertise your AGH server as DNS server for your lan and leave the phone on DHCP. How this is done depends on your router. The technical name for this option is "DHCP option 6".

Hardcoding your AGH server as DNS in wireguard is a perfectly acceptable solution if you want to be able to resolve local domains or just use your AGH filter lists on your phone when you are out and about. In fact it's what I would recommend for your wire guard config.

packoman

I found a work around, but not really a solution:

I added the IP if AdGuard as DNS server in the configuration of my Wireguard connection. It is now being used... I will see if this configuration does what I need (i.e. exclusive use of my AdGuard as DNS server).

Still... If anyone has a solution to the former problem, I would be very interested to hear it.

DeletedUser87

packoman your first approach obviously won't work. The second approach is the correct one. Private DNS is for publicly accessible DNS server (never host that yourself!) and the static IP settings need to be filled out completely to take effect (IP, CIDR, Gateway, DNS). If you want to use AdGuard Home when away from home, it has to be through the VPN configuration. And that's the correct solution!

packoman

DeletedUser87
Thanks for your reply. I don't understand your statement (sorry): "The second approach is the correct one."
Do you mean the "Private DNS" (which will not work with my private AdGuard instance, as you say) or configuring the DNS in the Wireguard configuration?

DeletedUser87

packoman second approach implies second comment, as in using a VPN.