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RedHat 9 (Linux i386) - man page for host (redhat section 1)

HOST(1) 										  HOST(1)

NAME
       host - DNS lookup utility

SYNOPSIS
       host  [	-aCdlnrTwv ]  [ -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.  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. The argument is provided for compatibility with older implemementations. This option
       is equivalent to making a query of type AXFR.

       The -n option specifies that reverse lookups of IPv6  addresses	should	use  the  IP6.INT
       domain  and  "nibble"  labels  as  defined in RFC1886.  The default is to use IP6.ARPA and
       binary labels as defined in RFC2874.

       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  behaviour  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 -t option is used to select the query type.	type can be any  recognised  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 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.

       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.

FILES
       /etc/resolv.conf

SEE ALSO
       dig(1), named(8).

BIND9					   Jun 30, 2000 				  HOST(1)


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