Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
HOST(1)				     BIND9			       HOST(1)

       host - DNS lookup utility

       host [-aCdlnrsTwv] [-c class] [-N ndots]	[-R number] [-t	type]
	    [-W	wait] [-m flag]	[-4] [-6] {name} [server]

       host is a simple	utility	for performing DNS lookups. It is normally
       used to convert names to	IP addresses and vice versa. When no arguments
       or options are given, host prints a short summary of its	command	line
       arguments and options.

       name is the domain name that is to be looked up.	It can also be a
       dotted-decimal IPv4 address or a	colon-delimited	IPv6 address, in which
       case host will by default perform a reverse lookup for that address.
       server is an optional argument which is either the name or IP address
       of the name server that host should query instead of the	server or
       servers listed in /etc/resolv.conf.

       The -a (all) option is equivalent to setting the	-v option and asking
       host to make a query of type ANY.

       When the	-C option is used, host	will 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.

       The -c option instructs to make a DNS query of class class. This	can be
       used to lookup Hesiod or	Chaosnet class resource	records. The default
       class is	IN (Internet).

       Verbose output is generated by host when	the -d or -v option is used.
       The two options are equivalent. They have been provided for backwards
       compatibility. In previous versions, the	-d option switched on
       debugging traces	and -v enabled verbose output.

       List mode is selected by	the -l option. This makes host perform a zone
       transfer	for zone name. Transfer	the zone printing out the NS, PTR and
       address records (A/AAAA). If combined with -a all records will be

       The -i option specifies that reverse lookups of IPv6 addresses should
       use the IP6.INT domain as defined in RFC1886. The default is to use

       The -N option sets the number of	dots that have to be in	name for it to
       be considered absolute. The default value is that defined using the
       ndots statement in /etc/resolv.conf, or 1 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.

       The number of UDP retries for a lookup can be changed with the -R
       option.	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 will default to 1.

       Non-recursive queries can be made via the -r option. 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 name. The -r	option enables host to mimic
       the behavior of a name server by	making non-recursive queries and
       expecting to receive answers to those queries that are usually
       referrals to other name servers.

       By default, host	uses UDP when making queries. The -T option makes it
       use a TCP connection when querying the name server. TCP will be
       automatically selected for queries that require it, such	as zone
       transfer	(AXFR) requests.

       The -4 option forces host to only use IPv4 query	transport. The -6
       option forces host to only use IPv6 query transport.

       The -t option is	used to	select the query type.	type can be any
       recognized query	type: CNAME, NS, SOA, SIG, KEY,	AXFR, etc. When	no
       query type is specified,	host automatically selects an appropriate
       query type. By default, it looks	for A, AAAA, and MX records, but if
       the -C option was given,	queries	will be	made for SOA records, and if
       name is a dotted-decimal	IPv4 address or	colon-delimited	IPv6 address,
       host will query for PTR records.	If a query type	of IXFR	is chosen the
       starting	serial number can be specified by appending an equal followed
       by the starting serial number (e.g. -t IXFR=12345678).

       The time	to wait	for a reply can	be controlled through the -W and -w
       options.	The -W option makes host wait for wait seconds.	If wait	is
       less than one, the wait interval	is set to one second. When the -w
       option is used, host will effectively wait forever for a	reply. The
       time to wait for	a response will	be set to the number of	seconds	given
       by the hardware's maximum value for an integer quantity.

       The -s option tells host	not to send the	query to the next nameserver
       if any server responds with a SERVFAIL response,	which is the reverse
       of normal stub resolver behavior.

       The -m can be used to set the memory usage debugging flags record,
       usage and trace.

       If host has been	built with IDN (internationalized domain name)
       support,	it can accept and display non-ASCII domain names.  host
       appropriately converts character	encoding of domain name	before sending
       a request to DNS	server or displaying a reply from the server. If you'd
       like to turn off	the IDN	support	for some reason, defines the
       IDN_DISABLE environment variable. The IDN support is disabled if	the
       variable	is set when host runs.


       dig(1), named(8).

       Copyright (C) 2004, 2005, 2007-2009 Internet Systems Consortium,	Inc.
       Copyright (C) 2000-2002 Internet	Software Consortium.

BIND9				 Jun 30, 2000			       HOST(1)


Want to link to this manual page? Use this URL:

home | help