Find authoritative nameservers via NS chase dig
Query each authoritative NS directly; reveals SOA serial mismatches between them
dig +nssearch example.com
more dig
all 11 commands →
Attempt a zone transfer (AXFR)
dig axfr @ns1.example.com example.com
Validate DNSSEC chain with RRSIG
dig +dnssec +multi example.com @1.1.1.1
Trace delegation without DNSSEC noise
dig +trace +nodnssec example.com
Compare answers from two resolvers
diff <(dig +short @1.1.1.1 example.com) <(dig +short @8.8.8.8 example.com)
Reverse PTR lookup for IPv6
dig -x 2606:4700:4700::1111 +short