Nslookup

networking
A Unix utility program, originally by Andrew Cherenson, for querying Internet domain name servers. The basic use is to find the IP address corresponding to a given hostname (or vice versa). By changing the query type (e.g. “set type=CNAME”) other types of information can be obtained including CNAME – the canonical name for an alias; HINFO – the host CPU and operating system type; MINFO – mailbox or mail list information; MX – mail exchanger information; NS – the name server for the named zone; PTR – the hostname if the query is an IP address, otherwise the pointer to other information; SOA the domain’s start-of-authority information; TXT – text information; UINFO – user information; WKS – supported well-known services. Other types (ANY, AXFR, MB, MD, MF, NULL) are described in RFC 1035.
(ftp://src.doc.ic.ac.uk/computing/operating-systems/unix/bsd-sources/usr.sbin/named/tools/nslookup/).
(1994-10-27)