Did you know?
You can use the dnstop command on Linux, FreeBSD/Unix to monitor both authoritative & caching DNS server network traffic. It can show:

Source & Destination IP addresses
Query types
Response codes
Opcodes
Top level domains and more.

See https://www.cyberciti.biz/faq/dnstop-monitor-bind-dns-server-dns-network-traffic-from-a-shell-prompt/ for more info.