Annotation of src/usr.bin/dig/dig.1, Revision 1.2
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1.2 ! florian 17: .Dd $Mdocdate: February 7 2020 $
1.1 florian 18: .Dt DIG 1
19: .Os
20: .Sh NAME
21: .Nm dig
22: .Nd DNS lookup utility
23: .Sh SYNOPSIS
24: .Nm
25: .Op Pf @ Ar server
26: .Op Fl 46hiuv
27: .Op Fl b Ar address Ns Op Pf # Ar port
28: .Op Fl c Ar class
29: .Op Fl f Ar file
30: .Op Fl k Ar keyfile
31: .Op Fl p Ar port
32: .Op Fl q Ar name
33: .Op Fl t Ar type
34: .Op Fl x Ar addr
35: .Op Fl y Oo Ar hmac : Oc Ns Ar name : Ns Ar key
36: .Op Ar name
37: .Op Ar type
38: .Op Ar class
39: .Op Pf + Ar queryopt ...
40: .Sh DESCRIPTION
41: The
42: .Nm
43: command is a flexible tool for interrogating DNS name servers.
44: It performs DNS lookups and displays the answers that are returned from the name
45: servers that were queried.
46: Although
47: .Nm
48: is normally used with command line arguments, it also has a batch mode of
49: operation for reading lookup requests from a file.
50: When no command line arguments or options are given,
51: .Nm
52: will perform an NS query for '.' (the root).
53: .Pp
54: A typical invocation of
55: .Nm
56: looks like:
57: .Pp
58: .Dl dig @server [options] name type [class] [+queryopt]
59: .Bl -tag -width +queryopt
60: .It Pf @ Ar server
61: The name or IP address of the name server to query.
62: When the argument is a hostname,
63: .Nm
64: resolves that name before querying that name server.
65: If no
66: .Ar server
67: argument is provided,
68: .Nm
69: will try each of the servers listed in
70: .Xr resolv.conf 5 .
71: If no usable addresses are found,
72: .Nm
73: will send the query to the local host.
74: The reply from the name server that responds is displayed.
75: .It Ar name
76: The name of the resource record that is to be looked up.
77: .It Ar type
78: The type of query, as documented for
79: .Fl t .
80: The default is
81: .Cm A .
82: .It Ar class
83: The query class, as documented for
84: .Fl c .
85: The default is
86: .Cm IN .
87: .It Pf + Ar queryopt
88: One or more query options,
89: as documented in
90: .Sx QUERY OPTIONS ,
91: below.
92: .El
93: .Pp
94: The options are as follows:
95: .Bl -tag -width Ds
96: .It Fl 4
97: Use IPv4 only.
98: .It Fl 6
99: Use IPv6 only.
100: .It Fl b Ar address Ns Op Pf # Ar port
101: Set the source IP address of the query.
102: The
103: .Ar address
104: must be a valid address on one of the host's network interfaces, or
105: "0.0.0.0" or "::". An optional port may be specified by appending
106: "#<port>".
107: .It Fl c Ar class
108: Set the query class.
109: The default is
110: .Cm IN ;
111: other classes are
112: .Cm HS
113: for Hesiod records and
114: .Cm CH
115: for Chaosnet records.
116: .It Fl f Ar file
117: Batch mode:
118: .Nm
119: reads a list of lookup requests to process from the given
120: .Ar file .
121: Each line in the file should be organized in the same way they would be
122: presented as queries to
123: .Nm
124: using the command-line interface.
125: .It Fl h
126: Display a brief summary of command line arguments and options.
127: .It Fl i
128: Do reverse IPv6 lookups using the obsolete RFC 1886 IP6.INT domain, which is no
129: longer in use.
130: Obsolete bit string label queries (RFC 2874) are not attempted.
131: .It Fl k Ar keyfile
132: Sign queries using TSIG using a key read from the given file.
133: When using TSIG authentication with
134: .Nm ,
135: the name server that is queried needs to know the key and algorithm that is
136: being used.
137: In BIND, this is done by providing appropriate
138: .Ic key
139: and
140: .Ic server
141: statements in
142: .Pa named.conf .
143: .It Fl p Ar port
144: Send the query to a non-standard port on the server, instead of the defaut port
145: 53.
146: This option would be used to test a name server that has been configured to
147: listen for queries on a non-standard port number.
148: .It Fl q Ar name
149: The domain name to query.
150: This is useful to distinguish the
151: .Ar name
152: from other arguments.
153: .It Fl t Ar type
154: The resource record type to query.
155: It can be any valid query type.
156: If it is a resource record type supported in BIND 9, it can be given by the
157: type mnemonic (such as
158: .Cm NS
159: or
160: .Cm AAAA ) .
161: The default query type is
162: .Cm A ,
163: unless the
164: .Fl x
165: option is supplied to indicate a reverse lookup.
166: A zone transfer can be requested by specifying a type of
167: .Cm AXFR .
168: When an incremental zone transfer is required, set the
169: .Ar type
170: to
171: .Cm IXFR Ns = Ns Ar N .
172: The incremental zone transfer will contain the changes made to the zone since
173: the serial number in the zone's SOA record was
174: .Ar N .
175: .Pp
176: All resource record types can be expressed as
177: .Cm TYPE Ns Ar nn ,
178: where
179: .Ar nn
180: is the number of the type.
181: If the resource record type is not supported in BIND 9, the result will be
182: displayed as described in RFC 3597.
183: .It Fl u
184: Print query times in microseconds instead of milliseconds.
185: .It Fl v
186: Print the version number and exit.
187: .It Fl x Ar addr
188: Simplified reverse lookups, for mapping addresses to names.
189: The
190: .Ar addr
191: is an IPv4 address in dotted-decimal notation, or a colon-delimited IPv6
192: address.
193: When the
194: .Fl x
195: is used, there is no need to provide the
196: .Ar name ,
197: .Ar class
198: and
199: .Ar type
200: arguments.
201: .Nm
202: automatically performs a lookup for a name like
203: .Ql 94.2.0.192.in-addr.arpa
204: and sets the query type and class to
205: .Cm PTR
206: and
207: .Cm IN
208: respectively.
209: IPv6 addresses are looked up using nibble format under the IP6.ARPA domain
210: (but see also the
211: .Fl i
212: option).
213: .It Fl y Xo
214: .Op Ar hmac : Ns
215: .Ar keyname : Ns
216: .Ar secret
217: .Xc
218: Sign queries using TSIG with the given authentication key.
219: .Ar keyname
220: is the name of the key, and
221: .Ar secret
222: is the base64 encoded shared secret.
223: .Ar hmac
224: is the name of the key algorithm;
225: valid choices are
226: .Ql hmac-md5 ,
227: .Ql hmac-sha1 ,
228: .Ql hmac-sha224 ,
229: .Ql hmac-sha256 ,
230: .Ql hmac-sha384 ,
231: or
232: .Ql hmac-sha512 .
233: If
234: .Ar hmac
235: is not specified, the default is
236: .Ql hmac-md5
237: or if MD5 was disabled
238: .Ql hmac-sha256 .
239: .Pp
240: NOTE: You should use the
241: .Fl k
242: option and
243: avoid the
244: .Fl y
245: option, because
246: with
247: .Fl y
248: the shared secret is supplied as a command line argument in clear text.
249: This may be visible in the output from
250: .Xr ps 1
251: or in a history file maintained by the user's shell.
252: .El
253: .Pp
254: The
255: .Cm IN
256: and
257: .Cm CH
258: class names overlap with the IN and CH top level domain names.
259: Either use the
260: .Fl t
261: and
262: .Fl c
263: options to specify the type and class, use the
264: .Fl q
265: to specify the domain name, or use "IN." and "CH." when looking up these top
266: level domains.
267: .Sh QUERY OPTIONS
268: .Nm
269: provides a number of query options which affect the way in which lookups are
270: made and the results displayed.
271: Some of
272: these set or reset flag bits in the query header, some determine which sections
273: of the answer get printed, and others determine the timeout and retry
274: strategies.
275: .Pp
276: Each query option is identified by a keyword preceded by a plus sign
277: .Pq Cm + .
278: Some keywords set or reset an option.
279: These may be preceded by the string
280: .Cm no
281: to negate the meaning of that keyword.
282: Other keywords assign values to options like the timeout interval.
283: They have the form
284: .Cm + Ns Ar keyword Ns = Ns Ar value .
285: Keywords may be abbreviated, provided the abbreviation is unambiguous; for
286: example,
287: .Cm +cd
288: is equivalent
289: to
290: .Cm +cdflag .
291: The query options are:
292: .Bl -tag -width Ds
293: .It Xo
294: .Cm + Ns
295: .Op Cm no Ns
296: .Cm aaflag
297: .Xc
298: A synonym for
299: .Xo
300: .Cm + Ns
301: .Op Cm no Ns
302: .Cm aaonly .
303: .Xc
304: .It Xo
305: .Cm + Ns
306: .Op Cm no Ns
307: .Cm aaonly
308: .Xc
309: Set the "aa" flag in the query (off by default).
310: .It Xo
311: .Cm + Ns
312: .Op Cm no Ns
313: .Cm additional
314: .Xc
315: Display the additional section of a reply (on by default).
316: .It Xo
317: .Cm + Ns
318: .Op Cm no Ns
319: .Cm adflag
320: .Xc
321: Set the AD (authentic data) bit in the query (on by default).
322: This requests the server to return whether all of the answer and authority
323: sections have all been validated as secure according to the security policy of
324: the server.
325: AD=1 indicates that all records have been validated as secure and the answer is
326: not from an OPT-OUT range.
327: AD=0 indicates that some part of the answer was insecure or not validated.
328: .It Xo
329: .Cm + Ns
330: .Op Cm no Ns
331: .Cm all
332: .Xc
333: Set or clear all display flags.
334: .It Xo
335: .Cm + Ns
336: .Op Cm no Ns
337: .Cm answer
338: .Xc
339: Display the answer section of a reply (on by default).
340: .It Xo
341: .Cm + Ns
342: .Op Cm no Ns
343: .Cm authority
344: .Xc
345: Display the authority section of a reply (on by default).
346: .It Xo
347: .Cm + Ns
348: .Op Cm no Ns
349: .Cm besteffort
350: .Xc
351: Attempt to display the contents of messages which are malformed (on by
352: default).
353: .It Cm +bufsize Ns = Ns Ar #
354: Set the UDP message buffer size advertised using EDNS0 to
355: .Ar #
356: bytes.
357: The maximum and minimum sizes of this buffer are 65535 and 0 respectively.
358: Values outside this range are rounded up or down appropriately.
359: Values other than zero will cause an EDNS query to be sent.
360: .It Xo
361: .Cm + Ns
362: .Op Cm no Ns
363: .Cm cdflag
364: .Xc
365: Set the CD (checking disabled) bit in the query (off by default).
366: This requests the server to not perform DNSSEC validation of responses.
367: .It Xo
368: .Cm + Ns
369: .Op Cm no Ns
370: .Cm class
371: .Xc
372: Display the CLASS when printing the record (on by default).
373: .It Xo
374: .Cm + Ns
375: .Op Cm no Ns
376: .Cm cmd
377: .Xc
378: Print an initial comment identifying the version of
379: .Nm
380: and the query options that have been applied (on by default).
381: .It Xo
382: .Cm + Ns
383: .Op Cm no Ns
384: .Cm comments
385: .Xc
386: Display comment lines in the output (on by default).
387: .It Xo
388: .Cm + Ns
389: .Op Cm no Ns
390: .Cm cookie Ns
391: .Op = Ns Ar value
392: .Xc
393: Send a COOKIE EDNS option, containing an optional
394: .Ar value
395: (off by default).
396: Replaying a COOKIE from a previous response will allow the server to
397: identify a previous client.
398: .Pp
399: .Cm +cookie
400: is automatically set when
401: .Cm +trace
402: is in use, to better emulate the default queries from a name server.
403: .Pp
404: This option was formerly called
405: .Xo
406: .Cm + Ns
407: .Op Cm no Ns
408: .Cm sit
409: .Xc
410: (Server Identity Token).
411: In BIND 9.10.0 through BIND 9.10.2,
412: it sent the experimental option code 65001.
413: This was changed to option code 10 in BIND 9.10.3 when the DNS
414: COOKIE option was allocated.
415: .Pp
416: The
417: .Xo
418: .Cm + Ns
419: .Op Cm no Ns
420: .Cm sit
421: .Xc
422: option is now deprecated, but has been retained as a synonym for
423: .Xo
424: .Cm + Ns
425: .Op Cm no Ns
426: .Cm cookie
427: .Xc
428: for backward compatibility within the BIND 9.10 branch.
429: .It Xo
430: .Cm + Ns
431: .Op Cm no Ns
432: .Cm crypto
433: .Xc
434: Display cryptographic fields in DNSSEC records (on by default).
435: The contents of these field are unnecessary to debug most DNSSEC validation
436: failures and removing them makes it easier to see the common failures.
437: When omitted they are replaced by the string "[omitted]" or in the DNSKEY case
438: the key id is displayed as the replacement, e.g. "[ key id = value ]".
439: .It Xo
440: .Cm + Ns
441: .Op Cm no Ns
442: .Cm defname
443: .Xc
444: Deprecated, treated as a synonym for
445: .Xo
446: .Cm + Ns
447: .Op Cm no Ns
448: .Cm search
449: .Xc .
450: .It Xo
451: .Cm + Ns
452: .Op Cm no Ns
453: .Cm dnssec
454: .Xc
455: Request DNSSEC records be sent by setting the DNSSEC OK bit (DO) in the OPT
456: record in the additional section of the query (off by default).
457: .It Cm +domain Ns = Ns Ar name
458: Set the search list to contain the single domain
459: .Ar name ,
460: as if specified in a
461: .Ic domain
462: directive in
463: .Xr resolv.conf 5 ,
464: and enable search list processing as if the
465: .Cm +search
466: option were given (off by default).
467: .It Xo
468: .Cm + Ns
469: .Op Cm no Ns
470: .Cm edns Ns
471: .Op = Ns Ar #
472: .Xc
473: Use EDNS in the query (on by default).
474: A version may also be specified, from 0 (the default) to 255.
475: .Cm +noedns
476: disables EDNS and clears the remembered version.
477: .It Cm +ednsflags Ns Op = Ns Ar #
478: Set the must-be-zero EDNS flags bits (Z bits)
479: to the specified value (0 by default).
480: Decimal, hex and octal encodings are accepted.
481: Setting a named flag (e.g. DO) will silently be ignored.
482: .It Xo
483: .Cm + Ns
484: .Op Cm no Ns
485: .Cm ednsnegotiation
486: .Xc
487: Enable EDNS version negotiation (off by default).
488: .It Xo
489: .Cm + Ns
490: .Op Cm no Ns
491: .Cm ednsopt Ns
492: .Op = Ns Ar code Ns Op : Ns Ar value
493: .Xc
494: Specify EDNS option with code point
495: .Ar code
496: and optionally payload of
497: .Ar value
498: as a hexadecimal string.
499: .Ar code
500: can be
501: either an EDNS option name (for example,
502: .Cm NSID
503: or
504: .Cm ECS ) ,
505: or an arbitrary numeric value.
506: .Cm +noednsopt
507: clears the EDNS options to be sent.
508: .It Xo
509: .Cm + Ns
510: .Op Cm no Ns
511: .Cm expire
512: .Xc
513: Send an EDNS Expire option (off by default).
514: .It Xo
515: .Cm + Ns
516: .Op Cm no Ns
517: .Cm fail
518: .Xc
519: Do not try the next server if you receive a SERVFAIL.
520: This option is on by default,
521: which is the reverse of normal stub resolver behavior.
522: .It Xo
523: .Cm + Ns
524: .Op Cm no Ns
525: .Cm identify
526: .Xc
527: Show the IP address and port number that supplied the answer (off by default).
528: This option has no effect unless the
529: .Cm +short
530: option is enabled.
531: .It Xo
532: .Cm + Ns
533: .Op Cm no Ns
534: .Cm idnout
535: .Xc
536: Convert puny code on output.
537: This version of
538: .Nm
539: does not support IDN.
540: .It Xo
541: .Cm + Ns
542: .Op Cm no Ns
543: .Cm ignore
544: .Xc
545: Ignore truncation in UDP responses.
546: This option is off by default, which means truncated responses
547: cause retrying with TCP.
548: .It Xo
549: .Cm + Ns
550: .Op Cm no Ns
551: .Cm keepopen
552: .Xc
553: Keep the TCP socket open between queries and reuse it.
554: This option is off by default, which means that a new TCP socket
555: is created for each lookup.
556: .It Xo
557: .Cm + Ns
558: .Op Cm no Ns
559: .Cm multiline
560: .Xc
561: Print records like the SOA records in a verbose multi-line format with
562: human-readable comments.
563: This option is off by default, which means that each record is
564: printed on a single line to facilitate machine parsing of the
565: .Nm
566: output.
567: .It Cm +ndots Ns = Ns Ar #
568: Set the number of dots that have to appear in
569: .Ar name
570: to
571: .Ar #
572: for it to be considered absolute.
573: The default value is that defined using the ndots statement in
574: .Xr resolv.conf 5 ,
575: or 1 if no ndots statement is present.
576: Names with fewer dots are interpreted as relative names and will be searched
577: for in the domains listed in the
578: .Cm search
579: or
580: .Cm domain
581: directive in
582: .Xr resolv.conf 5
583: if
584: .Cm +search
585: is set.
586: .It Xo
587: .Cm + Ns
588: .Op Cm no Ns
589: .Cm nsid
590: .Xc
591: Include an EDNS name server ID request when sending a query (off by default).
592: .It Xo
593: .Cm + Ns
594: .Op Cm no Ns
595: .Cm nssearch
596: .Xc
597: Attempt to find the authoritative name servers for the zone
598: containing the name being looked up and display the SOA record
599: that each name server has for the zone (off by default).
600: .It Xo
601: .Cm + Ns
602: .Op Cm no Ns
603: .Cm onesoa
604: .Xc
605: Print only one (starting) SOA record when performing an
606: .Cm AXFR .
607: This option is off by default, which means that both the starting
608: and the ending SOA records are printed.
609: .It Xo
610: .Cm + Ns
611: .Op Cm no Ns
612: .Cm opcode Ns = Ns
613: .Ar #
614: .Xc
615: Set or restore the DNS message opcode to the specified value,
616: which can be
617: .Cm QUERY Pq the default ,
618: .Cm IQUERY ,
619: .Cm STATUS ,
620: .Cm NOTIFY ,
621: .Cm UPDATE ,
622: or an integer number in the range from 0 to 15.
623: .It Xo
624: .Cm + Ns
625: .Op Cm no Ns
626: .Cm qr
627: .Xc
628: Print the query as it is sent (off by default).
629: .It Xo
630: .Cm + Ns
631: .Op Cm no Ns
632: .Cm question
633: .Xc
634: Print the question section of a query as a comment when an answer
635: is returned (on by default).
636: .It Xo
637: .Cm + Ns
638: .Op Cm no Ns
639: .Cm rdflag
640: .Xc
641: A synonym for
642: .Xo
643: .Cm + Ns
644: .Op Cm no Ns
645: .Cm recurse
646: .Xc .
647: .It Xo
648: .Cm + Ns
649: .Op Cm no Ns
650: .Cm recurse
651: .Xc
652: Set the RD (recursion desired) bit in the query (on by default).
653: Recursion is automatically disabled when the
654: .Cm +nssearch
655: or
656: .Cm +trace
657: query options are used.
658: .It Cm +retry Ns = Ns Ar #
659: Set the number of times to retry UDP queries to server to
660: .Ar # .
661: The default is 2.
662: Unlike
663: .Cm +tries ,
664: this does not include the initial query.
665: .It Xo
666: .Cm + Ns
667: .Op Cm no Ns
668: .Cm rrcomments
669: .Xc
670: Display per-record comments in the output (for example,
671: human-readable key information about DNSKEY records).
672: The default is
673: .Cm +rrcomments
674: if
675: .Cm +multiline
676: mode is active or
677: .Cm +norrcomments
678: otherwise.
679: .It Xo
680: .Cm + Ns
681: .Op Cm no Ns
682: .Cm search
683: .Xc
684: Use the search list defined by the searchlist or domain directive in
685: .Xr resolv.conf 5 ,
686: if any (off by default).
687: \&'ndots' from
688: .Xr resolv.conf 5
689: (default 1), which may be overridden by
690: .Cm +ndots ,
691: determines if the name will be treated as relative or not and hence whether a
692: search is eventually performed or not.
693: .It Xo
694: .Cm + Ns
695: .Op Cm no Ns
696: .Cm short
697: .Xc
698: Provide a terse answer (off by default).
699: .It Xo
700: .Cm + Ns
701: .Op Cm no Ns
702: .Cm showsearch
703: .Xc
704: Perform a search showing intermediate results (off by default).
705: .It Xo
706: .Cm + Ns
707: .Op Cm no Ns
708: .Cm split Ns = Ns Ar #
709: .Xc
710: Split long hex- or base64-formatted fields in resource records into chunks of
711: .Ar #
712: characters (where
713: .Ar #
714: is rounded up to the nearest multiple of 4).
715: .Cm +nosplit
716: or
717: .Cm +split Ns =0
718: causes fields not to be split at all.
719: The default is 56 characters, or 44 characters when
720: .Cm +multiline
721: mode is active.
722: .It Xo
723: .Cm + Ns
724: .Op Cm no Ns
725: .Cm stats
726: .Xc
727: Print statistics:
728: when the query was made, the size of the reply and so on (on by default).
729: .It Xo
730: .Cm + Ns
731: .Op Cm no Ns
732: .Cm subnet Ns = Ns
733: .Ar addr Ns
734: .Op / Ns Ar prefix
735: .Xc
736: Send an EDNS Client Subnet option with the specified IP address or
737: network prefix (off by default).
738: .Pp
739: .Nm
740: .Cm +subnet Ns =0.0.0.0/0,
741: or simply
742: .Nm
743: .Cm +subnet Ns =0
744: for short, sends an EDNS CLIENT-SUBNET option with an empty address and a
745: source prefix-length of zero, which signals a resolver that the client's address
746: information must
747: .Em not
748: be used when resolving this query.
749: .It Xo
750: .Cm + Ns
751: .Op Cm no Ns
752: .Cm tcp
753: .Xc
754: Use TCP when querying name servers (off by default).
755: .Cm IXFR Ns = Ns Ar N
756: queries use TCP unless it is explicitly disabled with
757: .Cm +notcp .
758: .Cm AXFR
759: queries always use TCP.
760: .It Cm +timeout Ns = Ns Ar #
761: Set the timeout for a query to
762: .Ar #
763: seconds.
764: The default is 5 seconds for UDP and 10 seconds for TCP.
765: An attempt to set
766: .Ar #
767: to less than 1 will result in a query timeout of 1 second being applied.
768: .It Xo
769: .Cm + Ns
770: .Op Cm no Ns
771: .Cm trace
772: .Xc
773: Trace the delegation path from the root name servers for the name
774: being looked up (off by default).
775: .Pp
776: When tracing is enabled,
777: .Nm
778: makes iterative queries to resolve the name being looked up.
779: It will follow referrals from the root servers, showing the answer from each
780: server that was used to resolve the lookup.
781: .Pp
782: If @server is also specified, it affects only the initial query for the root
783: zone name servers.
784: .Pp
785: .Cm +dnssec
786: is also set when
787: .Cm +trace
788: is set to better emulate the default queries from a name server.
789: .It Cm +tries Ns = Ns Ar #
790: Set the number of times to try UDP queries to server to
791: .Ar # .
792: The default is 3.
793: If
794: .Ar #
795: is less than or equal to zero, the number of tries is silently rounded up to 1.
796: .It Xo
797: .Cm + Ns
798: .Op Cm no Ns
799: .Cm ttlid
800: .Xc
801: Display the TTL when printing the record (on by default).
802: .It Xo
803: .Cm + Ns
804: .Op Cm no Ns
805: .Cm vc
806: .Xc
807: Use TCP when querying name servers.
808: This alternate syntax to
809: .Xo
810: .Cm + Ns
811: .Op Cm no Ns
812: .Cm tcp
813: .Xc
814: is provided for backwards compatibility.
815: The "vc" stands for "virtual circuit".
816: .El
817: .Sh MULTIPLE QUERIES
818: The BIND 9 implementation of
819: .Nm
820: supports specifying multiple queries on the command line (in addition to
821: supporting the
822: .Fl f
823: batch file option).
824: Each of those queries can be supplied with its own set of flags, options and
825: query options.
826: .Pp
827: In this case, each
828: .Ar query
829: argument represent an individual query in the command-line syntax described
830: above.
831: Each consists of any of the standard options and flags, the name to be looked
832: up, an optional query type and class and any query options that should be
833: applied to that query.
834: .Pp
835: A global set of query options, which should be applied to all queries, can
836: also be supplied.
837: These global query options must precede the first tuple of name, class, type,
838: options, flags, and query options supplied on the command line.
839: Any global query options (except the
840: .Xo
841: .Cm + Ns
842: .Op Cm no Ns
843: .Cm cmd
844: .Xc
845: option) can be overridden by a query-specific set of query options.
846: For example:
847: .Bd -literal -offset indent
848: dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr
849: .Ed
850: .Pp
851: shows how
852: .Nm
853: could be used from the command line to make three lookups: an ANY query for
854: www.isc.org, a reverse lookup of 127.0.0.1 and a query for the NS records of
855: isc.org.
856: A global query option of
857: .Cm +qr
858: is applied, so that
859: .Nm
860: shows the initial query it made for each lookup.
861: The final query has a local query option of
862: .Cm +noqr
863: which means that
864: .Nm
865: will not print the initial query when it looks up the NS records for
866: isc.org.
867: .Sh FILES
868: .Bl -tag -width Ds
869: .It Pa /etc/resolv.conf
870: Resolver configuration file.
871: .El
872: .Sh SEE ALSO
873: .Xr host 1 ,
874: .Xr resolv.conf 5
875: .Sh STANDARDS
876: .Rs
877: .%A P. Mockapetris
878: .%D November 1987
879: .%R RFC 1035
880: .%T Domain Names - Implementation and Specification
881: .Re
882: .Sh AUTHORS
883: .An -nosplit
884: .An Internet Systems Consortium, Inc .
885: .Sh BUGS
886: There are probably too many query options.
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