host.1 (2010 09)

h
host(1) host(1)
(BIND 9.3)
NAME
host - DNS lookup utility
SYNOPSIS
host [-4|-6][
-aCdilrTwv][-c class ][-N ndots ][-R
number][-t type ][-W wait ]
name [server ]
DESCRIPTION
host is a simple utility for performing DNS lookups. It is normally used to convert names to IP
addresses and vice versa. With no options or operands,
host prints an annotated usage summary.
Options
-4 Use only the IPv4 query transport.
-6 Use only the IPv6 query transport.
-a Equivalent to using -v -t ANY
.
-C Attempt to display the SOA
records for zone name from all the listed authoritative name
servers for that zone. The list of name servers is defined by the
NS records that are found for
the zone.
-c class Make a DNS query of class class . This can be used to look up class resource records. The
values for class are:
IN The Internet class (default).
CH, CHAOS The MIT Chaosnet class.
HS, HESIOD The MIT Athena Hesiod class.
The class values are case-insensitive.
-d Generate verbose output. Now equivalent to the -v option. -d is provided for backwards
compatibility. In previous versions, it switched on debugging traces.
-i Use the IP6.INT domain, as defined in RFC 1886, to perform reverse lookups of IPv6
addresses. The default is to use IP6.ARPA.
-l Select list mode. host performs a zone transfer for zone name. Transfer the zone, printing
out the NS, PTR and address records (A/AAAA). If -l
is combined with -a, all records will be
printed.
-N ndots Set the number of dots that have to be in name for it to be considered absolute. The default
value is defined using the ndots statement in /etc/resolv.conf
,oris1 if no ndots
statement is present. Names with fewer dots are interpreted as relative names and will be
searched for in the domains listed in the search or domain directive in
/etc/resolv.conf.
-R number
Set the number of UDP retries for a lookup. number indicates how many times host will
repeat a query that does not get answered. The default number of retries is 1. If number is
negative or zero, the number of retries is set to 1.
-r Make nonrecursive queries. Setting this option clears the RD (recursion desired) bit in the
query which host makes. This should mean that the name server receiving the query will not
attempt to resolve the name operand.
This option enables
host to mimic the behavior of a name server by making nonrecursive
queries and expecting to receive answers to those queries that are usually referrals to other
name servers.
-T Use a TCP connection when querying the name server. TCP is automatically selected for
queries that require it, such as zone transfer (AXFR) requests. By default host uses UDP
when making queries.
-t type Select the query type. type can be any recognized query type: A, AAAA, ANY, AXFR, CNAME,
IXFR, KEY, NS, PTR, SIG, SOA, and so on. For potential values, see the set querytype
command in nslookup (1) and the Zone File discussion in named.conf (4).
The type values are case-insensitive.
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1