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6aa2272cc4af77e605ba2c4a4781f8567408b7e3pquerna [<!ENTITY mdash "—">]>
1c223a87ddbe004229f784c72d64d1a6d8487bcccolm - Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
1c223a87ddbe004229f784c72d64d1a6d8487bcccolm - Copyright (C) 2000-2002 Internet Software Consortium.
e6a970c1049c5053321d183ffc391de62b17afd7colm - Permission to use, copy, modify, and/or distribute this software for any
e6a970c1049c5053321d183ffc391de62b17afd7colm - purpose with or without fee is hereby granted, provided that the above
e6a970c1049c5053321d183ffc391de62b17afd7colm - copyright notice and this permission notice appear in all copies.
7b621044ee03c0c140c2ba6fdab7d2dfdb2b9f4acolm - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
7b621044ee03c0c140c2ba6fdab7d2dfdb2b9f4acolm - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
7b621044ee03c0c140c2ba6fdab7d2dfdb2b9f4acolm - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
89ebbccde2b87b469b9d6fdb606eeb943c12a824colm - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
89ebbccde2b87b469b9d6fdb606eeb943c12a824colm - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
89ebbccde2b87b469b9d6fdb606eeb943c12a824colm - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
89ebbccde2b87b469b9d6fdb606eeb943c12a824colm - PERFORMANCE OF THIS SOFTWARE.
b38565306421ff53e9f7499bc728d6df5cec294dpquerna<!-- $Id: host.docbook,v 1.17 2008/04/04 23:23:33 marka Exp $ -->
6aa2272cc4af77e605ba2c4a4781f8567408b7e3pquerna <refentryinfo>
dface6840439ab84a36749f40e7773ebfdc2066ejorton </refentryinfo>
1febae173a82bc2a71c3c0ba4105cf674000791bjim </refmeta>
1febae173a82bc2a71c3c0ba4105cf674000791bjim <refnamediv>
2b409b0583ef844d6f85002160cbc6df95b9afa8jerenkrantz </refnamediv>
1392b9997000dceb6aca39da0a1e6405ccb6f0a6jerenkrantz <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
1392b9997000dceb6aca39da0a1e6405ccb6f0a6jerenkrantz </copyright>
4b0a0ae3fd77f8fc8fd2a693be33ffe4d99cb94ajerenkrantz </copyright>
ee508128c414648982d1cca7801f63b01a0a4f8aminfrin <refsynopsisdiv>
ee508128c414648982d1cca7801f63b01a0a4f8aminfrin <cmdsynopsis>
f07ae092933846055c4ca046c5a65de83d79c9c6pquerna <arg><option>-c <replaceable class="parameter">class</replaceable></option></arg>
9b88ec397b4155f3ff79bf7c08de5f15d21765b3pquerna <arg><option>-N <replaceable class="parameter">ndots</replaceable></option></arg>
9b88ec397b4155f3ff79bf7c08de5f15d21765b3pquerna <arg><option>-R <replaceable class="parameter">number</replaceable></option></arg>
9b88ec397b4155f3ff79bf7c08de5f15d21765b3pquerna <arg><option>-t <replaceable class="parameter">type</replaceable></option></arg>
a42c13195a5c68d55f6b2bbf5b5e1e66ab45d5d4pquerna <arg><option>-W <replaceable class="parameter">wait</replaceable></option></arg>
a42c13195a5c68d55f6b2bbf5b5e1e66ab45d5d4pquerna <arg><option>-m <replaceable class="parameter">flag</replaceable></option></arg>
ede0584e7ec53cc1ea832c5c50281431d9ecc576pquerna </cmdsynopsis>
ede0584e7ec53cc1ea832c5c50281431d9ecc576pquerna </refsynopsisdiv>
4ec8ec67d57d820b15807fa4a23ddd0c351fa9efwrowe is a simple utility for performing DNS lookups.
4d3ee33c1047b89e2860fbf095c77ad245910983wrowe It is normally used to convert names to IP addresses and vice versa.
4ec8ec67d57d820b15807fa4a23ddd0c351fa9efwrowe When no arguments or options are given,
4d3ee33c1047b89e2860fbf095c77ad245910983wrowe prints a short summary of its command line arguments and options.
b59ae7ab0c7b5c37f145e416d61add8fd433be04wrowe <para><parameter>name</parameter> is the domain name that is to be
4d3ee33c1047b89e2860fbf095c77ad245910983wrowe up. It can also be a dotted-decimal IPv4 address or a colon-delimited
b59ae7ab0c7b5c37f145e416d61add8fd433be04wrowe IPv6 address, in which case <command>host</command> will by
42167da203d969a1402cf7ce09c14586c04af1dfjim perform a reverse lookup for that address.
42167da203d969a1402cf7ce09c14586c04af1dfjim <parameter>server</parameter> is an optional argument which
e62b34b26eb8e82bf6f06ff99a08e304b48792ecpquerna the name or IP address of the name server that <command>host</command>
e62b34b26eb8e82bf6f06ff99a08e304b48792ecpquerna should query instead of the server or servers listed in
ceeb4b77f172b9d0125f1b4b323675d700b2c43bminfrin The <option>-a</option> (all) option is equivalent to setting the
ceeb4b77f172b9d0125f1b4b323675d700b2c43bminfrin <option>-v</option> option and asking <command>host</command> to make
ceeb4b77f172b9d0125f1b4b323675d700b2c43bminfrin a query of type ANY.
9152b0c4366af633c4b7982af01bd9a821f410d5pquerna When the <option>-C</option> option is used, <command>host</command>
87d944bf70927764edf8ef69e46d3b4b8fa09131pquerna will attempt to display the SOA records for zone
424c1a743525e9c5008e29b39a99363723409a1dtrawick authoritative name
424c1a743525e9c5008e29b39a99363723409a1dtrawick servers for that zone. The list of name servers is defined by the NS
424c1a743525e9c5008e29b39a99363723409a1dtrawick records that are found for the zone.
39dbd3f60b93f5e0fbf46d9ae237f6742e113442pquerna The <option>-c</option> option instructs to make a DNS query of class
39dbd3f60b93f5e0fbf46d9ae237f6742e113442pquerna <parameter>class</parameter>. This can be used to lookup
89211a3153be8b03353c3bfbca45fed67cb80f0bpquerna Chaosnet class resource records. The default class is IN (Internet).
89211a3153be8b03353c3bfbca45fed67cb80f0bpquerna Verbose output is generated by <command>host</command> when
89211a3153be8b03353c3bfbca45fed67cb80f0bpquerna <option>-d</option> or <option>-v</option> option is used. The two
a14ccf0f7e9b44c6848334823542a1799577f669pquerna options are equivalent. They have been provided for backwards
a14ccf0f7e9b44c6848334823542a1799577f669pquerna compatibility. In previous versions, the <option>-d</option> option
a14ccf0f7e9b44c6848334823542a1799577f669pquerna switched on debugging traces and <option>-v</option> enabled verbose
a2e37e48efb113e8e4f9d9ca9c8286aaac6c936cpquerna List mode is selected by the <option>-l</option> option. This makes
007ba11dc68651df7f872f35947ae82a595d9e02pquerna <command>host</command> perform a zone transfer for zone
007ba11dc68651df7f872f35947ae82a595d9e02pquerna <parameter>name</parameter>. Transfer the zone printing out
007ba11dc68651df7f872f35947ae82a595d9e02pquerna the NS, PTR
25059ddf3044ffa8dd3432ab8e2f941023054407trawick and address records (A/AAAA). If combined with <option>-a</option>
25059ddf3044ffa8dd3432ab8e2f941023054407trawick all records will be printed.
44ca834b970b454b844efb96f219bdf49fee71e5trawick option specifies that reverse lookups of IPv6 addresses should
eb8430fd3bc941c0b3ba8bba3884b7fc464bf458pquerna use the IP6.INT domain as defined in RFC1886.
eb8430fd3bc941c0b3ba8bba3884b7fc464bf458pquerna The default is to use IP6.ARPA.
1f9e65264b1ff249fa071e6aae32c0bb52f9c634trawick The <option>-N</option> option sets the number of dots that have to be
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes in <parameter>name</parameter> for it to be considered
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes absolute. The
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes default value is that defined using the ndots statement in
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes <filename>/etc/resolv.conf</filename>, or 1 if no ndots
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes statement is
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes present. Names with fewer dots are interpreted as relative names and
fde88bb682426885c679198ee130d2d5a29e8c0fbnicholes will be searched for in the domains listed in the <type>search</type>
d66ac514cc15e99228d72c56c6c3daf25da8d360niq The number of UDP retries for a lookup can be changed with the
d66ac514cc15e99228d72c56c6c3daf25da8d360niq <option>-R</option> option. <parameter>number</parameter>
e23b77006a8b079c0ad52e42ba2029e759455b8fjorton how many times <command>host</command> will repeat a query
e23b77006a8b079c0ad52e42ba2029e759455b8fjorton not get answered. The default number of retries is 1. If
e23b77006a8b079c0ad52e42ba2029e759455b8fjorton <parameter>number</parameter> is negative or zero, the
b597281295360dba8ac57b7606c5f5c1ef2b69b0trawick retries will default to 1.
22c347c08cd77d5e2c32536b467b389fd33d631fpquerna Non-recursive queries can be made via the <option>-r</option> option.
22c347c08cd77d5e2c32536b467b389fd33d631fpquerna Setting this option clears the <type>RD</type> — recursion
8c46f9f81ae6357dc97560d6d85154f19cf251aejim desired — bit in the query which <command>host</command> makes.
b6e2b36d6972a0e243368eb567e91d511fb40b1bbnicholes This should mean that the name server receiving the query will not
b6e2b36d6972a0e243368eb567e91d511fb40b1bbnicholes attempt to resolve <parameter>name</parameter>. The
b6e2b36d6972a0e243368eb567e91d511fb40b1bbnicholes <option>-r</option> option enables <command>host</command>
b6e2b36d6972a0e243368eb567e91d511fb40b1bbnicholes the behavior of a name server by making non-recursive queries and
ad4a5834dfdf9488af4ac3238ea4d8b18dce49acpquerna expecting to receive answers to those queries that are usually
e5882a36d7756850cc829f5f2286120b877458b1pquerna referrals to other name servers.
8b7594c66e764f5cd3506b6f2459497ab65a8b03pquerna By default <command>host</command> uses UDP when making
8c46f9f81ae6357dc97560d6d85154f19cf251aejim queries. The
8c46f9f81ae6357dc97560d6d85154f19cf251aejim <option>-T</option> option makes it use a TCP connection when querying
20f1b1a67eef5ab0f3295608c89964a7dca4fdd1pquerna the name server. TCP will be automatically selected for queries that
20f1b1a67eef5ab0f3295608c89964a7dca4fdd1pquerna require it, such as zone transfer (AXFR) requests.
599c5abcc7fec60611956f56b732eca033c287d2pquerna The <option>-4</option> option forces <command>host</command> to only
599c5abcc7fec60611956f56b732eca033c287d2pquerna use IPv4 query transport. The <option>-6</option> option forces
e76fdcdfb8994ad70776526f50fa013b3e9a6033bnicholes <command>host</command> to only use IPv6 query transport.
eb9b491d7b262dad572ec2f1f75eea592283f81apquerna The <option>-t</option> option is used to select the query type.
1ef90d1763e489969ec7a01c77bcb158ece5ae83jorton <parameter>type</parameter> can be any recognized query
c5cb4c9e7c8696907ddebab2a0037717c710b0f6jorton type: CNAME,
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive NS, SOA, SIG, KEY, AXFR, etc. When no query type is specified,
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive <command>host</command> automatically selects an appropriate
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive type. By default it looks for A, AAAA, and MX records, but if the
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive <option>-C</option> option was given, queries will be made for SOA
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive dotted-decimal IPv4
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive address or colon-delimited IPv6 address, <command>host</command> will
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive query for PTR records. If a query type of IXFR is chosen the starting
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive serial number can be specified by appending an equal followed by the
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive starting serial number (e.g. -t IXFR=12345678).
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive The time to wait for a reply can be controlled through the
6d00a5e2c08ddbff9614ecc17a1c085462811f89slive <option>-W</option> and <option>-w</option> options. The
4f6e78091b3f45a5782389ae25b62516a7a0c842bnicholes <option>-W</option> option makes <command>host</command>
4f6e78091b3f45a5782389ae25b62516a7a0c842bnicholes <parameter>wait</parameter> seconds. If <parameter>wait</parameter>
4f6e78091b3f45a5782389ae25b62516a7a0c842bnicholes is less than one, the wait interval is set to one second. When the
4f6e78091b3f45a5782389ae25b62516a7a0c842bnicholes <option>-w</option> option is used, <command>host</command>
7d15331eeb5429d7148d13d6fd914a641bf1c000pquerna effectively wait forever for a reply. The time to wait for a response
7d15331eeb5429d7148d13d6fd914a641bf1c000pquerna will be set to the number of seconds given by the hardware's maximum
e9be3aacfd6c0a1208e6c91a133be92ed0f94fe1bnicholes value for an integer quantity.
1d14622beee568462689b2bbc6a9e0e9b6a40583striker The <option>-s</option> option tells <command>host</command>
1d14622beee568462689b2bbc6a9e0e9b6a40583striker <emphasis>not</emphasis> to send the query to the next nameserver
6e5f5644328bf50c3aa295d0ab20903369010829gregames if any server responds with a SERVFAIL response, which is the
6e5f5644328bf50c3aa295d0ab20903369010829gregames reverse of normal stub resolver behavior.
e978097e0bf2ae161b6f9dde40eaf089bf046c89ake The <option>-m</option> can be used to set the memory usage debugging
275419d6395e6f072962fb701b89accaff1f3690jerenkrantz <parameter>record</parameter>, <parameter>usage</parameter> and
8bdea88407c848c1c2693655e2f8b23abde12307bnicholes If <command>host</command> has been built with IDN (internationalized
275419d6395e6f072962fb701b89accaff1f3690jerenkrantz domain name) support, it can accept and display non-ASCII domain names.
8e7fb6968047a527d1ccde25ad2aed20da5150ddjerenkrantz <command>host</command> appropriately converts character encoding of
8e7fb6968047a527d1ccde25ad2aed20da5150ddjerenkrantz domain name before sending a request to DNS server or displaying a
8e7fb6968047a527d1ccde25ad2aed20da5150ddjerenkrantz reply from the server.
5a9fa4d75086e942f6e850e1a2e96c4c27a845d0jerenkrantz If you'd like to turn off the IDN support for some reason, defines
5a9fa4d75086e942f6e850e1a2e96c4c27a845d0jerenkrantz the <envar>IDN_DISABLE</envar> environment variable.
5a9fa4d75086e942f6e850e1a2e96c4c27a845d0jerenkrantz The IDN support is disabled if the variable is set when
36c8049de63c446926139936c3d195330a0539cetrawick </refsect1>
9174efb969475801d0dc88eee35aae40c748d450nd <refsect1>
8ff094bdec6a2e1c355c1e6e95e9952d4fae7766jerenkrantz <refentrytitle>dig</refentrytitle><manvolnum>1</manvolnum>
628cf3411e8a6d09e27b3666312e43832dda93f3jorton </citerefentry>,
628cf3411e8a6d09e27b3666312e43832dda93f3jorton <citerefentry>
628cf3411e8a6d09e27b3666312e43832dda93f3jorton <refentrytitle>named</refentrytitle><manvolnum>8</manvolnum>
f0d89a5a23222e031db8113478645f28688fa748jorton </citerefentry>.
f0d89a5a23222e031db8113478645f28688fa748jorton </refsect1>
f0d89a5a23222e031db8113478645f28688fa748jorton - Local variables:
f0d89a5a23222e031db8113478645f28688fa748jorton - mode: sgml