New Around Here
Initially, I've configured RT-AC86U (192.168.2.1) to ignore DNS provided by the ISP router/modem, and it works ok with 126.96.36.199 and 188.8.131.52, likewise "nslookup google.com 192.168.2.1" works fine. Yet when I switch ISP router/modem into bridge mode (and RT-AC86U gets public IP on WAN), "nslookup google.com 192.168.2.1" breaks, while querying 184.108.40.206 still works. Likewise, internet works but Speedtest even resolves list of servers to connect to with a significant delay. It would seem that DNS server on RT-AC86U just stops working when ISP router/modem is in bridge mode.