dig - DNS lookup utility
Display the IP address of a host:
dig www.google.com A
Display the hostname of an IP address:
dig 172.217.28.142
Display IPV6 DNS servers:
dig iana.org AAAA
Display the MX (mail exchanger) of a domain/host name:
dig google.com MX
Display the NS (name server) of a domain name:
dig google.com NS
Show the SOA (Start of Authority) records for DNS zone name:
dig google.com SOA
Display the short version of a query:
dig +short google.com NS
Display the route from host to DNS server:
dig +trace google.com