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3 - Copyright (C) 2000-2002 Internet Software Consortium.
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47 >host -- DNS lookup utility</DIV
49 CLASS="REFSYNOPSISDIV"
112 is a simple utility for performing DNS lookups.
113 It is normally used to convert names to IP addresses and vice versa.
114 When no arguments or options are given,
119 prints a short summary of its command line arguments and options.</P
124 > is the domain name that is to be looked
125 up. It can also be a dotted-decimal IPv4 address or a colon-delimited
126 IPv6 address, in which case <B
130 perform a reverse lookup for that address.
134 > is an optional argument which is either
135 the name or IP address of the name server that <B
139 should query instead of the server or servers listed in
142 >/etc/resolv.conf</TT
148 > (all) option is equivalent to setting the
152 > option and asking <B
156 a query of type ANY.</P
165 will attempt to display the SOA records for zone
169 > from all the listed authoritative name
170 servers for that zone. The list of name servers is defined by the NS
171 records that are found for the zone.</P
176 > option instructs to make a DNS query of class
180 >. This can be used to lookup Hesiod or
181 Chaosnet class resource records. The default class is IN (Internet).</P
183 >Verbose output is generated by <B
193 > option is used. The two
194 options are equivalent. They have been provided for backwards
195 compatibility. In previous versions, the <VAR
199 switched on debugging traces and <VAR
205 >List mode is selected by the <VAR
212 > perform a zone transfer for zone
216 >. Transfer the zone printing out the NS, PTR
217 and address records (A/AAAA). If combined with <VAR
221 all records will be printed. </P
227 option specifies that reverse lookups of IPv6 addresses should
228 use the IP6.INT domain as defined in RFC1886.
229 The default is to use IP6.ARPA.</P
234 > option sets the number of dots that have to be
238 > for it to be considered absolute. The
239 default value is that defined using the ndots statement in
242 >/etc/resolv.conf</TT
243 >, or 1 if no ndots statement is
244 present. Names with fewer dots are interpreted as relative names and
245 will be searched for in the domains listed in the <SPAN
255 >/etc/resolv.conf</TT
258 >The number of UDP retries for a lookup can be changed with the
269 > will repeat a query that does
270 not get answered. The default number of retries is 1. If
274 > is negative or zero, the number of
275 retries will default to 1.</P
277 >Non-recursive queries can be made via the <VAR
281 Setting this option clears the <SPAN
285 desired — bit in the query which <B
289 This should mean that the name server receiving the query will not
290 attempt to resolve <VAR
301 the behaviour of a name server by making non-recursive queries and
302 expecting to receive answers to those queries that are usually
303 referrals to other name servers.</P
308 > uses UDP when making queries. The
312 > option makes it use a TCP connection when querying
313 the name server. TCP will be automatically selected for queries that
314 require it, such as zone transfer (AXFR) requests.</P
323 use IPv4 query transport. The <VAR
330 > to only use IPv6 query transport.</P
335 > option is used to select the query type.
339 > can be any recognised query type: CNAME,
340 NS, SOA, SIG, KEY, AXFR, etc. When no query type is specified,
344 > automatically selects an appropriate query
345 type. By default it looks for A records, but if the
349 > option was given, queries will be made for SOA
353 > is a dotted-decimal IPv4
354 address or colon-delimited IPv6 address, <B
358 query for PTR records. If a query type of IXFR is chosen the starting
359 serial number can be specified by appending an equal followed by the
360 starting serial number (e.g. -t IXFR=12345678).</P
362 >The time to wait for a reply can be controlled through the
384 is less than one, the wait interval is set to one second. When the
392 effectively wait forever for a reply. The time to wait for a response
393 will be set to the number of seconds given by the hardware's maximum
394 value for an integer quantity.</P
406 >/etc/resolv.conf</TT
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