i have got following configuration for DNS upstreaming
Client 1 --|
Client 2 --|
Client 3 --|—> DNS Server Teltonika Router → DNS Server AdGuard Home → DNS Server WAN
Client N --|
The DNS Server AdGuard Home is responsible for filtering DNS queries.
I want the DNS Server AdGuard to show the client IP in its frontend so that I know which client requested which domain. Unfortunately, only the IP of the Teltonika Router is shown.
The problem itself is well known, I have to add the --add-subnet parameter to dnsmasq to add an EDNS Client subnet to the DNS packet.
In blogs, I figured out, that Teltonika saves the dnsmasq config file in /etc/config/dhcp.
I thought it would be enough to add following entry to the config file…
option addsubnet ‘32,128’
(for 32 subnet mask IPv4 and 128 subnet mask IPv6, i.e. the exact client IP is added to the DNS request)
However, after using tcpdump and wireshark it seems as if the info is not added.
Does anyone know which parameter I have to add to which section in which file to tell dnsmasq to add EDNS ECS info?