Dnsmasq add-subnet option (ECS/EDNS0 Client Subnet)

Installing and Using OpenWrt
1

Hi. I've configured dnsmasq forwarding DNS request to an external server (adguardhome) in other pc. It's working, but i can't see client's IP or names in adguard (all requests are logged with router IP). In theory this can be solved adding --add-subnet=32,128 option to dnsmasq, but i think that it's not possible (or isn't documented) for openwrt. Anybody know how to solve this problem?

conf-file=/etc/dnsmasq.conf
dhcp-authoritative
domain-needed
strict-order
localise-queries
read-ethers
enable-ubus=dnsmasq
expand-hosts
bind-dynamic
local-service
cache-size=1000
port=53
edns-packet-max=1232
domain=lan
local=/lan/
server=192.168.3.2
server=1.1.1.1
addn-hosts=/tmp/hosts
dhcp-leasefile=/tmp/dhcp.leases
resolv-file=/tmp/resolv.conf.d/resolv.conf.auto
add-mac
dhcp-broadcast=tag:needs-broadcast
conf-dir=/tmp/dnsmasq.d
user=dnsmasq
group=dnsmasq

I know that I can announce the DNS server with DHCP option, but I don't want this because I want to have a failover DNS server (a second forward in dnsmasq). This part is working.

Thanks

2

You can add that option directly to /etc/dnsmasq.conf, but beware you would also be sending that client info to 1.1.1.1 when that server is used by dnsmasq.

1 Like
3

I've added as "add-subnet=32,128", restarted dnsmasq but... no luck...

4

I don’t use AGH, but it appears it does not yet recognize EDNS client subnet in queries.