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21 <!-- Id: dig.docbook,v 1.45 2009/02/02 04:41:28 marka Exp -->
22 <refentry id="man.dig">
24 <refentryinfo>
25 <date>Jun 30, 2000</date>
26 </refentryinfo>
28 <refmeta>
29 <refentrytitle>dig</refentrytitle>
30 <manvolnum>1</manvolnum>
31 <refmiscinfo>BIND9</refmiscinfo>
32 </refmeta>
34 <refnamediv>
35 <refname>dig</refname>
36 <refpurpose>DNS lookup utility</refpurpose>
37 </refnamediv>
39 <docinfo>
40 <copyright>
41 <year>2004</year>
42 <year>2005</year>
43 <year>2006</year>
44 <year>2007</year>
45 <year>2008</year>
46 <year>2009</year>
47 <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
48 </copyright>
49 <copyright>
50 <year>2000</year>
51 <year>2001</year>
52 <year>2002</year>
53 <year>2003</year>
54 <holder>Internet Software Consortium.</holder>
55 </copyright>
56 </docinfo>
58 <refsynopsisdiv>
59 <cmdsynopsis>
60 <command>dig</command>
61 <arg choice="opt">@server</arg>
62 <arg><option>-b <replaceable class="parameter">address</replaceable></option></arg>
63 <arg><option>-c <replaceable class="parameter">class</replaceable></option></arg>
64 <arg><option>-f <replaceable class="parameter">filename</replaceable></option></arg>
65 <arg><option>-k <replaceable class="parameter">filename</replaceable></option></arg>
66 <arg><option>-m</option></arg>
67 <arg><option>-p <replaceable class="parameter">port#</replaceable></option></arg>
68 <arg><option>-q <replaceable class="parameter">name</replaceable></option></arg>
69 <arg><option>-t <replaceable class="parameter">type</replaceable></option></arg>
70 <arg><option>-x <replaceable class="parameter">addr</replaceable></option></arg>
71 <arg><option>-y <replaceable class="parameter"><optional>hmac:</optional>name:key</replaceable></option></arg>
72 <arg><option>-4</option></arg>
73 <arg><option>-6</option></arg>
74 <arg choice="opt">name</arg>
75 <arg choice="opt">type</arg>
76 <arg choice="opt">class</arg>
77 <arg choice="opt" rep="repeat">queryopt</arg>
78 </cmdsynopsis>
80 <cmdsynopsis>
81 <command>dig</command>
82 <arg><option>-h</option></arg>
83 </cmdsynopsis>
85 <cmdsynopsis>
86 <command>dig</command>
87 <arg choice="opt" rep="repeat">global-queryopt</arg>
88 <arg choice="opt" rep="repeat">query</arg>
89 </cmdsynopsis>
90 </refsynopsisdiv>
92 <refsect1>
93 <title>DESCRIPTION</title>
94 <para><command>dig</command>
95 (domain information groper) is a flexible tool
96 for interrogating DNS name servers. It performs DNS lookups and
97 displays the answers that are returned from the name server(s) that
98 were queried. Most DNS administrators use <command>dig</command> to
99 troubleshoot DNS problems because of its flexibility, ease of use and
100 clarity of output. Other lookup tools tend to have less functionality
101 than <command>dig</command>.
102 </para>
104 <para>
105 Although <command>dig</command> is normally used with
106 command-line
107 arguments, it also has a batch mode of operation for reading lookup
108 requests from a file. A brief summary of its command-line arguments
109 and options is printed when the <option>-h</option> option is given.
110 Unlike earlier versions, the BIND 9 implementation of
111 <command>dig</command> allows multiple lookups to be issued
112 from the
113 command line.
114 </para>
116 <para>
117 Unless it is told to query a specific name server,
118 <command>dig</command> will try each of the servers listed
119 in
120 <filename>/etc/resolv.conf</filename>.
121 </para>
123 <para>
124 When no command line arguments or options are given,
125 <command>dig</command> will perform an NS query for "." (the root).
126 </para>
128 <para>
129 It is possible to set per-user defaults for <command>dig</command> via
130 <filename>${HOME}/.digrc</filename>. This file is read and
131 any options in it
132 are applied before the command line arguments.
133 </para>
135 <para>
136 The IN and CH class names overlap with the IN and CH top level
137 domains names. Either use the <option>-t</option> and
138 <option>-c</option> options to specify the type and class,
139 use the <option>-q</option> the specify the domain name, or
140 use "IN." and "CH." when looking up these top level domains.
141 </para>
143 </refsect1>
145 <refsect1>
146 <title>SIMPLE USAGE</title>
148 <para>
149 A typical invocation of <command>dig</command> looks like:
150 <programlisting> dig @server name type </programlisting>
151 where:
153 <variablelist>
155 <varlistentry>
156 <term><constant>server</constant></term>
157 <listitem>
158 <para>
159 is the name or IP address of the name server to query. This can
160 be an IPv4
161 address in dotted-decimal notation or an IPv6
162 address in colon-delimited notation. When the supplied
163 <parameter>server</parameter> argument is a
164 hostname,
165 <command>dig</command> resolves that name before
166 querying that name
167 server. If no <parameter>server</parameter>
168 argument is provided,
169 <command>dig</command> consults <filename>/etc/resolv.conf</filename>
170 and queries the name servers listed there. The reply from the
171 name
172 server that responds is displayed.
173 </para>
174 </listitem>
175 </varlistentry>
177 <varlistentry>
178 <term><constant>name</constant></term>
179 <listitem>
180 <para>
181 is the name of the resource record that is to be looked up.
182 </para>
183 </listitem>
184 </varlistentry>
186 <varlistentry>
187 <term><constant>type</constant></term>
188 <listitem>
189 <para>
190 indicates what type of query is required —
191 ANY, A, MX, SIG, etc.
192 <parameter>type</parameter> can be any valid query
193 type. If no
194 <parameter>type</parameter> argument is supplied,
195 <command>dig</command> will perform a lookup for an
196 A record.
197 </para>
198 </listitem>
199 </varlistentry>
201 </variablelist>
202 </para>
204 </refsect1>
206 <refsect1>
207 <title>OPTIONS</title>
209 <para>
210 The <option>-b</option> option sets the source IP address of the query
211 to <parameter>address</parameter>. This must be a valid
212 address on
213 one of the host's network interfaces or "0.0.0.0" or "::". An optional
214 port
215 may be specified by appending "#<port>"
216 </para>
218 <para>
219 The default query class (IN for internet) is overridden by the
220 <option>-c</option> option. <parameter>class</parameter> is
221 any valid
222 class, such as HS for Hesiod records or CH for Chaosnet records.
223 </para>
225 <para>
226 The <option>-f</option> option makes <command>dig </command>
227 operate
228 in batch mode by reading a list of lookup requests to process from the
229 file <parameter>filename</parameter>. The file contains a
230 number of
231 queries, one per line. Each entry in the file should be organized in
232 the same way they would be presented as queries to
233 <command>dig</command> using the command-line interface.
234 </para>
236 <para>
237 The <option>-m</option> option enables memory usage debugging.
238 <!-- It enables ISC_MEM_DEBUGTRACE and ISC_MEM_DEBUGRECORD
239 documented in include/isc/mem.h -->
240 </para>
242 <para>
243 If a non-standard port number is to be queried, the
244 <option>-p</option> option is used. <parameter>port#</parameter> is
245 the port number that <command>dig</command> will send its
246 queries
247 instead of the standard DNS port number 53. This option would be used
248 to test a name server that has been configured to listen for queries
249 on a non-standard port number.
250 </para>
252 <para>
253 The <option>-4</option> option forces <command>dig</command>
254 to only
255 use IPv4 query transport. The <option>-6</option> option forces
256 <command>dig</command> to only use IPv6 query transport.
257 </para>
259 <para>
260 The <option>-t</option> option sets the query type to
261 <parameter>type</parameter>. It can be any valid query type
262 which is
263 supported in BIND 9. The default query type is "A", unless the
264 <option>-x</option> option is supplied to indicate a reverse lookup.
265 A zone transfer can be requested by specifying a type of AXFR. When
266 an incremental zone transfer (IXFR) is required,
267 <parameter>type</parameter> is set to <literal>ixfr=N</literal>.
268 The incremental zone transfer will contain the changes made to the zone
269 since the serial number in the zone's SOA record was
270 <parameter>N</parameter>.
271 </para>
273 <para>
274 The <option>-q</option> option sets the query name to
275 <parameter>name</parameter>. This useful do distinguish the
276 <parameter>name</parameter> from other arguments.
277 </para>
279 <para>
280 Reverse lookups — mapping addresses to names — are simplified by the
281 <option>-x</option> option. <parameter>addr</parameter> is
282 an IPv4
283 address in dotted-decimal notation, or a colon-delimited IPv6 address.
284 When this option is used, there is no need to provide the
285 <parameter>name</parameter>, <parameter>class</parameter> and
286 <parameter>type</parameter> arguments. <command>dig</command>
287 automatically performs a lookup for a name like
288 <literal>11.12.13.10.in-addr.arpa</literal> and sets the
289 query type and
290 class to PTR and IN respectively. By default, IPv6 addresses are
291 looked up using nibble format under the IP6.ARPA domain.
292 To use the older RFC1886 method using the IP6.INT domain
293 specify the <option>-i</option> option. Bit string labels (RFC2874)
294 are now experimental and are not attempted.
295 </para>
297 <para>
298 To sign the DNS queries sent by <command>dig</command> and
299 their
300 responses using transaction signatures (TSIG), specify a TSIG key file
301 using the <option>-k</option> option. You can also specify the TSIG
302 key itself on the command line using the <option>-y</option> option;
303 <parameter>hmac</parameter> is the type of the TSIG, default HMAC-MD5,
304 <parameter>name</parameter> is the name of the TSIG key and
305 <parameter>key</parameter> is the actual key. The key is a
306 base-64
307 encoded string, typically generated by
308 <citerefentry>
309 <refentrytitle>dnssec-keygen</refentrytitle><manvolnum>8</manvolnum>
310 </citerefentry>.
312 Caution should be taken when using the <option>-y</option> option on
313 multi-user systems as the key can be visible in the output from
314 <citerefentry>
315 <refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum>
316 </citerefentry>
317 or in the shell's history file. When
318 using TSIG authentication with <command>dig</command>, the name
319 server that is queried needs to know the key and algorithm that is
320 being used. In BIND, this is done by providing appropriate
321 <command>key</command> and <command>server</command> statements in
322 <filename>named.conf</filename>.
323 </para>
325 </refsect1>
327 <refsect1>
328 <title>QUERY OPTIONS</title>
330 <para><command>dig</command>
331 provides a number of query options which affect
332 the way in which lookups are made and the results displayed. Some of
333 these set or reset flag bits in the query header, some determine which
334 sections of the answer get printed, and others determine the timeout
335 and retry strategies.
336 </para>
338 <para>
339 Each query option is identified by a keyword preceded by a plus sign
340 (<literal>+</literal>). Some keywords set or reset an
341 option. These may be preceded
342 by the string <literal>no</literal> to negate the meaning of
343 that keyword. Other
344 keywords assign values to options like the timeout interval. They
345 have the form <option>+keyword=value</option>.
346 The query options are:
348 <variablelist>
350 <varlistentry>
351 <term><option>+[no]tcp</option></term>
352 <listitem>
353 <para>
354 Use [do not use] TCP when querying name servers. The default
355 behavior is to use UDP unless an AXFR or IXFR query is
356 requested, in
357 which case a TCP connection is used.
358 </para>
359 </listitem>
360 </varlistentry>
362 <varlistentry>
363 <term><option>+[no]vc</option></term>
364 <listitem>
365 <para>
366 Use [do not use] TCP when querying name servers. This alternate
367 syntax to <parameter>+[no]tcp</parameter> is
368 provided for backwards
369 compatibility. The "vc" stands for "virtual circuit".
370 </para>
371 </listitem>
372 </varlistentry>
374 <varlistentry>
375 <term><option>+[no]ignore</option></term>
376 <listitem>
377 <para>
378 Ignore truncation in UDP responses instead of retrying with TCP.
379 By
380 default, TCP retries are performed.
381 </para>
382 </listitem>
383 </varlistentry>
385 <varlistentry>
386 <term><option>+domain=somename</option></term>
387 <listitem>
388 <para>
389 Set the search list to contain the single domain
390 <parameter>somename</parameter>, as if specified in
391 a
392 <command>domain</command> directive in
393 <filename>/etc/resolv.conf</filename>, and enable
394 search list
395 processing as if the <parameter>+search</parameter>
396 option were given.
397 </para>
398 </listitem>
399 </varlistentry>
401 <varlistentry>
402 <term><option>+[no]search</option></term>
403 <listitem>
404 <para>
405 Use [do not use] the search list defined by the searchlist or
406 domain
407 directive in <filename>resolv.conf</filename> (if
408 any).
409 The search list is not used by default.
410 </para>
411 </listitem>
412 </varlistentry>
414 <varlistentry>
415 <term><option>+[no]showsearch</option></term>
416 <listitem>
417 <para>
418 Perform [do not perform] a search showing intermediate
419 results.
420 </para>
421 </listitem>
422 </varlistentry>
424 <varlistentry>
425 <term><option>+[no]defname</option></term>
426 <listitem>
427 <para>
428 Deprecated, treated as a synonym for <parameter>+[no]search</parameter>
429 </para>
430 </listitem>
431 </varlistentry>
433 <varlistentry>
434 <term><option>+[no]aaonly</option></term>
435 <listitem>
436 <para>
437 Sets the "aa" flag in the query.
438 </para>
439 </listitem>
440 </varlistentry>
442 <varlistentry>
443 <term><option>+[no]aaflag</option></term>
444 <listitem>
445 <para>
446 A synonym for <parameter>+[no]aaonly</parameter>.
447 </para>
448 </listitem>
449 </varlistentry>
451 <varlistentry>
452 <term><option>+[no]adflag</option></term>
453 <listitem>
454 <para>
455 Set [do not set] the AD (authentic data) bit in the
456 query. This requests the server to return whether
457 all of the answer and authority sections have all
458 been validated as secure according to the security
459 policy of the server. AD=1 indicates that all records
460 have been validated as secure and the answer is not
461 from a OPT-OUT range. AD=0 indicate that some part
462 of the answer was insecure or not validated.
463 </para>
464 </listitem>
465 </varlistentry>
467 <varlistentry>
468 <term><option>+[no]cdflag</option></term>
469 <listitem>
470 <para>
471 Set [do not set] the CD (checking disabled) bit in the query.
472 This
473 requests the server to not perform DNSSEC validation of
474 responses.
475 </para>
476 </listitem>
477 </varlistentry>
479 <varlistentry>
480 <term><option>+[no]cl</option></term>
481 <listitem>
482 <para>
483 Display [do not display] the CLASS when printing the record.
484 </para>
485 </listitem>
486 </varlistentry>
488 <varlistentry>
489 <term><option>+[no]ttlid</option></term>
490 <listitem>
491 <para>
492 Display [do not display] the TTL when printing the record.
493 </para>
494 </listitem>
495 </varlistentry>
497 <varlistentry>
498 <term><option>+[no]recurse</option></term>
499 <listitem>
500 <para>
501 Toggle the setting of the RD (recursion desired) bit in the
502 query.
503 This bit is set by default, which means <command>dig</command>
504 normally sends recursive queries. Recursion is automatically
505 disabled
506 when the <parameter>+nssearch</parameter> or
507 <parameter>+trace</parameter> query options are
508 used.
509 </para>
510 </listitem>
511 </varlistentry>
513 <varlistentry>
514 <term><option>+[no]nssearch</option></term>
515 <listitem>
516 <para>
517 When this option is set, <command>dig</command>
518 attempts to find the
519 authoritative name servers for the zone containing the name
520 being
521 looked up and display the SOA record that each name server has
522 for the
523 zone.
524 </para>
525 </listitem>
526 </varlistentry>
528 <varlistentry>
529 <term><option>+[no]trace</option></term>
530 <listitem>
531 <para>
532 Toggle tracing of the delegation path from the root name servers
533 for
534 the name being looked up. Tracing is disabled by default. When
535 tracing is enabled, <command>dig</command> makes
536 iterative queries to
537 resolve the name being looked up. It will follow referrals from
538 the
539 root servers, showing the answer from each server that was used
540 to
541 resolve the lookup.
542 </para>
543 </listitem>
544 </varlistentry>
546 <varlistentry>
547 <term><option>+[no]cmd</option></term>
548 <listitem>
549 <para>
550 Toggles the printing of the initial comment in the output
551 identifying
552 the version of <command>dig</command> and the query
553 options that have
554 been applied. This comment is printed by default.
555 </para>
556 </listitem>
557 </varlistentry>
559 <varlistentry>
560 <term><option>+[no]short</option></term>
561 <listitem>
562 <para>
563 Provide a terse answer. The default is to print the answer in a
564 verbose form.
565 </para>
566 </listitem>
567 </varlistentry>
569 <varlistentry>
570 <term><option>+[no]identify</option></term>
571 <listitem>
572 <para>
573 Show [or do not show] the IP address and port number that
574 supplied the
575 answer when the <parameter>+short</parameter> option
576 is enabled. If
577 short form answers are requested, the default is not to show the
578 source address and port number of the server that provided the
579 answer.
580 </para>
581 </listitem>
582 </varlistentry>
584 <varlistentry>
585 <term><option>+[no]comments</option></term>
586 <listitem>
587 <para>
588 Toggle the display of comment lines in the output. The default
589 is to
590 print comments.
591 </para>
592 </listitem>
593 </varlistentry>
595 <varlistentry>
596 <term><option>+[no]stats</option></term>
597 <listitem>
598 <para>
599 This query option toggles the printing of statistics: when the
600 query
601 was made, the size of the reply and so on. The default
602 behavior is
603 to print the query statistics.
604 </para>
605 </listitem>
606 </varlistentry>
608 <varlistentry>
609 <term><option>+[no]qr</option></term>
610 <listitem>
611 <para>
612 Print [do not print] the query as it is sent.
613 By default, the query is not printed.
614 </para>
615 </listitem>
616 </varlistentry>
618 <varlistentry>
619 <term><option>+[no]question</option></term>
620 <listitem>
621 <para>
622 Print [do not print] the question section of a query when an
623 answer is
624 returned. The default is to print the question section as a
625 comment.
626 </para>
627 </listitem>
628 </varlistentry>
630 <varlistentry>
631 <term><option>+[no]answer</option></term>
632 <listitem>
633 <para>
634 Display [do not display] the answer section of a reply. The
635 default
636 is to display it.
637 </para>
638 </listitem>
639 </varlistentry>
641 <varlistentry>
642 <term><option>+[no]authority</option></term>
643 <listitem>
644 <para>
645 Display [do not display] the authority section of a reply. The
646 default is to display it.
647 </para>
648 </listitem>
649 </varlistentry>
651 <varlistentry>
652 <term><option>+[no]additional</option></term>
653 <listitem>
654 <para>
655 Display [do not display] the additional section of a reply.
656 The default is to display it.
657 </para>
658 </listitem>
659 </varlistentry>
661 <varlistentry>
662 <term><option>+[no]all</option></term>
663 <listitem>
664 <para>
665 Set or clear all display flags.
666 </para>
667 </listitem>
668 </varlistentry>
670 <varlistentry>
671 <term><option>+time=T</option></term>
672 <listitem>
673 <para>
675 Sets the timeout for a query to
676 <parameter>T</parameter> seconds. The default
677 timeout is 5 seconds.
678 An attempt to set <parameter>T</parameter> to less
679 than 1 will result
680 in a query timeout of 1 second being applied.
681 </para>
682 </listitem>
683 </varlistentry>
685 <varlistentry>
686 <term><option>+tries=T</option></term>
687 <listitem>
688 <para>
689 Sets the number of times to try UDP queries to server to
690 <parameter>T</parameter> instead of the default, 3.
691 If
692 <parameter>T</parameter> is less than or equal to
693 zero, the number of
694 tries is silently rounded up to 1.
695 </para>
696 </listitem>
697 </varlistentry>
699 <varlistentry>
700 <term><option>+retry=T</option></term>
701 <listitem>
702 <para>
703 Sets the number of times to retry UDP queries to server to
704 <parameter>T</parameter> instead of the default, 2.
705 Unlike
706 <parameter>+tries</parameter>, this does not include
707 the initial
708 query.
709 </para>
710 </listitem>
711 </varlistentry>
713 <varlistentry>
714 <term><option>+ndots=D</option></term>
715 <listitem>
716 <para>
717 Set the number of dots that have to appear in
718 <parameter>name</parameter> to <parameter>D</parameter> for it to be
719 considered absolute. The default value is that defined using
720 the
721 ndots statement in <filename>/etc/resolv.conf</filename>, or 1 if no
722 ndots statement is present. Names with fewer dots are
723 interpreted as
724 relative names and will be searched for in the domains listed in
725 the
726 <option>search</option> or <option>domain</option> directive in
727 <filename>/etc/resolv.conf</filename>.
728 </para>
729 </listitem>
730 </varlistentry>
732 <varlistentry>
733 <term><option>+bufsize=B</option></term>
734 <listitem>
735 <para>
736 Set the UDP message buffer size advertised using EDNS0 to
737 <parameter>B</parameter> bytes. The maximum and minimum sizes
738 of this buffer are 65535 and 0 respectively. Values outside
739 this range are rounded up or down appropriately.
740 Values other than zero will cause a EDNS query to be sent.
741 </para>
742 </listitem>
743 </varlistentry>
745 <varlistentry>
746 <term><option>+edns=#</option></term>
747 <listitem>
748 <para>
749 Specify the EDNS version to query with. Valid values
750 are 0 to 255. Setting the EDNS version will cause a
751 EDNS query to be sent. <option>+noedns</option> clears the
752 remembered EDNS version.
753 </para>
754 </listitem>
755 </varlistentry>
757 <varlistentry>
758 <term><option>+[no]multiline</option></term>
759 <listitem>
760 <para>
761 Print records like the SOA records in a verbose multi-line
762 format with human-readable comments. The default is to print
763 each record on a single line, to facilitate machine parsing
764 of the <command>dig</command> output.
765 </para>
766 </listitem>
767 </varlistentry>
769 <varlistentry>
770 <term><option>+[no]fail</option></term>
771 <listitem>
772 <para>
773 Do not try the next server if you receive a SERVFAIL. The
774 default is
775 to not try the next server which is the reverse of normal stub
776 resolver
777 behavior.
778 </para>
779 </listitem>
780 </varlistentry>
782 <varlistentry>
783 <term><option>+[no]besteffort</option></term>
784 <listitem>
785 <para>
786 Attempt to display the contents of messages which are malformed.
787 The default is to not display malformed answers.
788 </para>
789 </listitem>
790 </varlistentry>
792 <varlistentry>
793 <term><option>+[no]dnssec</option></term>
794 <listitem>
795 <para>
796 Requests DNSSEC records be sent by setting the DNSSEC OK bit
797 (DO)
798 in the OPT record in the additional section of the query.
799 </para>
800 </listitem>
801 </varlistentry>
803 <varlistentry>
804 <term><option>+[no]sigchase</option></term>
805 <listitem>
806 <para>
807 Chase DNSSEC signature chains. Requires dig be compiled with
808 -DDIG_SIGCHASE.
809 </para>
810 </listitem>
811 </varlistentry>
813 <varlistentry>
814 <term><option>+trusted-key=####</option></term>
815 <listitem>
816 <para>
817 Specifies a file containing trusted keys to be used with
818 <option>+sigchase</option>. Each DNSKEY record must be
819 on its own line.
820 </para>
821 <para>
822 If not specified, <command>dig</command> will look for
823 <filename>/etc/trusted-key.key</filename> then
824 <filename>trusted-key.key</filename> in the current directory.
825 </para>
826 <para>
827 Requires dig be compiled with -DDIG_SIGCHASE.
828 </para>
829 </listitem>
830 </varlistentry>
832 <varlistentry>
833 <term><option>+[no]topdown</option></term>
834 <listitem>
835 <para>
836 When chasing DNSSEC signature chains perform a top-down
837 validation.
838 Requires dig be compiled with -DDIG_SIGCHASE.
839 </para>
840 </listitem>
841 </varlistentry>
843 <varlistentry>
844 <term><option>+[no]nsid</option></term>
845 <listitem>
846 <para>
847 Include an EDNS name server ID request when sending a query.
848 </para>
849 </listitem>
850 </varlistentry>
853 </variablelist>
855 </para>
856 </refsect1>
858 <refsect1>
859 <title>MULTIPLE QUERIES</title>
861 <para>
862 The BIND 9 implementation of <command>dig </command>
863 supports
864 specifying multiple queries on the command line (in addition to
865 supporting the <option>-f</option> batch file option). Each of those
866 queries can be supplied with its own set of flags, options and query
867 options.
868 </para>
870 <para>
871 In this case, each <parameter>query</parameter> argument
872 represent an
873 individual query in the command-line syntax described above. Each
874 consists of any of the standard options and flags, the name to be
875 looked up, an optional query type and class and any query options that
876 should be applied to that query.
877 </para>
879 <para>
880 A global set of query options, which should be applied to all queries,
881 can also be supplied. These global query options must precede the
882 first tuple of name, class, type, options, flags, and query options
883 supplied on the command line. Any global query options (except
884 the <option>+[no]cmd</option> option) can be
885 overridden by a query-specific set of query options. For example:
886 <programlisting>
887 dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr
888 </programlisting>
889 shows how <command>dig</command> could be used from the
890 command line
891 to make three lookups: an ANY query for <literal>www.isc.org</literal>, a
892 reverse lookup of 127.0.0.1 and a query for the NS records of
893 <literal>isc.org</literal>.
895 A global query option of <parameter>+qr</parameter> is
896 applied, so
897 that <command>dig</command> shows the initial query it made
898 for each
899 lookup. The final query has a local query option of
900 <parameter>+noqr</parameter> which means that <command>dig</command>
901 will not print the initial query when it looks up the NS records for
902 <literal>isc.org</literal>.
903 </para>
905 </refsect1>
907 <refsect1>
908 <title>IDN SUPPORT</title>
909 <para>
910 If <command>dig</command> has been built with IDN (internationalized
911 domain name) support, it can accept and display non-ASCII domain names.
912 <command>dig</command> appropriately converts character encoding of
913 domain name before sending a request to DNS server or displaying a
914 reply from the server.
915 If you'd like to turn off the IDN support for some reason, defines
916 the <envar>IDN_DISABLE</envar> environment variable.
917 The IDN support is disabled if the variable is set when
918 <command>dig</command> runs.
919 </para>
920 </refsect1>
922 <refsect1>
923 <title>FILES</title>
924 <para><filename>/etc/resolv.conf</filename>
925 </para>
926 <para><filename>${HOME}/.digrc</filename>
927 </para>
928 </refsect1>
930 <refsect1>
931 <title>SEE ALSO</title>
932 <para><citerefentry>
933 <refentrytitle>host</refentrytitle><manvolnum>1</manvolnum>
934 </citerefentry>,
935 <citerefentry>
936 <refentrytitle>named</refentrytitle><manvolnum>8</manvolnum>
937 </citerefentry>,
938 <citerefentry>
939 <refentrytitle>dnssec-keygen</refentrytitle><manvolnum>8</manvolnum>
940 </citerefentry>,
941 <citetitle>RFC1035</citetitle>.
942 </para>
943 </refsect1>
945 <refsect1>
946 <title>BUGS</title>
947 <para>
948 There are probably too many query options.
949 </para>
950 </refsect1>
951 </refentry><!--
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