1MDIG(1)                             BIND 9                             MDIG(1)
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NAME

6       mdig - DNS pipelined lookup utility
7

SYNOPSIS

9       mdig  {@server}  [-f  filename]  [-h] [-v] [ [-4] | [-6] ] [-m] [-b ad‐
10       dress] [-p port#] [-c class] [-t type] [-i] [-x addr] [plusopt...]
11
12       mdig {-h}
13
14       mdig [@server] {global-opt...} { {local-opt...} {query} ...}
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DESCRIPTION

17       mdig is a multiple/pipelined query version of dig: instead  of  waiting
18       for  a  response  after  sending  each  query, it begins by sending all
19       queries. Responses are displayed in the order in  which  they  are  re‐
20       ceived, not in the order the corresponding queries were sent.
21
22       mdig  options  are  a  subset  of the dig options, and are divided into
23       "anywhere options," which can occur anywhere, "global  options,"  which
24       must  occur before the query name (or they are ignored with a warning),
25       and "local options," which apply to the next query on the command line.
26
27       The @server option is a mandatory global option. It is the name  or  IP
28       address of the name server to query. (Unlike dig, this value is not re‐
29       trieved from /etc/resolv.conf.) It can  be  an  IPv4  address  in  dot‐
30       ted-decimal notation, an IPv6 address in colon-delimited notation, or a
31       hostname. When the supplied server argument is  a  hostname,  mdig  re‐
32       solves that name before querying the name server.
33
34       mdig  provides  a number of query options which affect the way in which
35       lookups are made and the results displayed. Some of these set or  reset
36       flag bits in the query header, some determine which sections of the an‐
37       swer get printed, and others determine the timeout  and  retry  strate‐
38       gies.
39
40       Each  query  option  is identified by a keyword preceded by a plus sign
41       (+). Some keywords set or reset an option. These may be preceded by the
42       string  no to negate the meaning of that keyword. Other keywords assign
43       values to options like the timeout interval. They have the  form  +key‐
44       word=value.
45

ANYWHERE OPTIONS

47       -f     This  option  makes mdig operate in batch mode by reading a list
48              of lookup requests to process from the file filename.  The  file
49              contains  a  number  of queries, one per line. Each entry in the
50              file should be organized in the same way they would be presented
51              as queries to mdig using the command-line interface.
52
53       -h     This option causes mdig to print detailed help information, with
54              the full list of options, and exit.
55
56       -v     This option causes mdig to print the version number and exit.
57

GLOBAL OPTIONS

59       -4     This option forces mdig to only use IPv4 query transport.
60
61       -6     This option forces mdig to only use IPv6 query transport.
62
63       -b address
64              This option sets the source IP address of the query to  address.
65              This must be a valid address on one of the host's network inter‐
66              faces or "0.0.0.0" or "::". An optional port may be specified by
67              appending "#<port>"
68
69       -m     This option enables memory usage debugging.
70
71       -p port#
72              This  option  is  used  when a non-standard port number is to be
73              queried. port# is the port number that mdig  sends  its  queries
74              to,  instead  of the standard DNS port number 53. This option is
75              used to test a name server that has been  configured  to  listen
76              for queries on a non-standard port number.
77
78       The global query options are:
79
80       +[no]additional
81              This  option  displays [or does not display] the additional sec‐
82              tion of a reply. The default is to display it.
83
84       +[no]all
85              This option sets or clears all display flags.
86
87       +[no]answer
88              This option displays [or does not display] the answer section of
89              a reply. The default is to display it.
90
91       +[no]authority
92              This option displays [or does not display] the authority section
93              of a reply. The default is to display it.
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95       +[no]besteffort
96              This option attempts to display [or does not display]  the  con‐
97              tents  of  messages  which  are malformed. The default is to not
98              display malformed answers.
99
100       +burst This option delays queries until the start of the next second.
101
102       +[no]cl
103              This option displays [or does not display] the CLASS when print‐
104              ing the record.
105
106       +[no]comments
107              This  option toggles the display of comment lines in the output.
108              The default is to print comments.
109
110       +[no]continue
111              This option toggles continuation on errors (e.g. timeouts).
112
113       +[no]crypto
114              This option toggles  the  display  of  cryptographic  fields  in
115              DNSSEC  records. The contents of these fields are unnecessary to
116              debug most DNSSEC validation failures and removing them makes it
117              easier to see the common failures. The default is to display the
118              fields. When omitted, they are replaced by  the  string  "[omit‐
119              ted]";  in  the  DNSKEY case, the key ID is displayed as the re‐
120              placement, e.g., [ key id = value ].
121
122       +dscp[=value]
123              This option sets the DSCP code point to be used when sending the
124              query.  Valid DSCP code points are in the range [0...63]. By de‐
125              fault no code point is explicitly set.
126
127       +[no]multiline
128              This option toggles printing of records, like the  SOA  records,
129              in a verbose multi-line format with human-readable comments. The
130              default is to print each record on a single line, to  facilitate
131              machine parsing of the mdig output.
132
133       +[no]question
134              This option prints [or does not print] the question section of a
135              query when an answer is returned. The default is  to  print  the
136              question section as a comment.
137
138       +[no]rrcomments
139              This  option  toggles  the display of per-record comments in the
140              output (for example, human-readable key information about DNSKEY
141              records).  The  default  is  not to print record comments unless
142              multiline mode is active.
143
144       +[no]short
145              This option provides [or does not provide] a terse  answer.  The
146              default is to print the answer in a verbose form.
147
148       +split=W
149              This  option  splits long hex- or base64-formatted fields in re‐
150              source records into chunks of W characters (where W  is  rounded
151              up  to  the  nearest multiple of 4). +nosplit or +split=0 causes
152              fields not to be split. The default  is  56  characters,  or  44
153              characters when multiline mode is active.
154
155       +[no]tcp
156              This  option  uses  [or  does  not  use]  TCP when querying name
157              servers. The default behavior is to use UDP.
158
159       +[no]ttlid
160              This option displays [or does not display] the TTL when printing
161              the record.
162
163       +[no]ttlunits
164              This  option  displays [or does not display] the TTL in friendly
165              human-readable time units of "s", "m", "h", "d", and "w", repre‐
166              senting  seconds,  minutes, hours, days, and weeks. This implies
167              +ttlid.
168
169       +[no]vc
170              This option uses [or  does  not  use]  TCP  when  querying  name
171              servers. This alternate syntax to +[no]tcp is provided for back‐
172              wards compatibility. The vc stands for "virtual circuit".
173

LOCAL OPTIONS

175       -c class
176              This option sets the query class to class. It can be  any  valid
177              query  class  which  is  supported  in BIND 9. The default query
178              class is "IN".
179
180       -t type
181              This option sets the query type to type. It  can  be  any  valid
182              query  type which is supported in BIND 9. The default query type
183              is "A", unless the -x option is supplied to indicate  a  reverse
184              lookup with the "PTR" query type.
185
186       -x addr
187              Reverse lookups - mapping addresses to names - are simplified by
188              this option. addr is an IPv4 address in dotted-decimal notation,
189              or a colon-delimited IPv6 address. mdig automatically performs a
190              lookup for a query name like 11.12.13.10.in-addr.arpa  and  sets
191              the query type and class to PTR and IN respectively. By default,
192              IPv6 addresses are looked  up  using  nibble  format  under  the
193              IP6.ARPA domain.
194
195       The local query options are:
196
197       +[no]aaflag
198              This is a synonym for +[no]aaonly.
199
200       +[no]aaonly
201              This sets the aa flag in the query.
202
203       +[no]adflag
204              This  sets  [or does not set] the AD (authentic data) bit in the
205              query. This requests the server to return whether all of the an‐
206              swer  and  authority sections have all been validated as secure,
207              according to the security policy of the server.  AD=1  indicates
208              that all records have been validated as secure and the answer is
209              not from a OPT-OUT range. AD=0 indicates that some part  of  the
210              answer  was  insecure  or not validated.  This bit is set by de‐
211              fault.
212
213       +bufsize=B
214              This sets the UDP message buffer size advertised using EDNS0  to
215              B  bytes. The maximum and minimum sizes of this buffer are 65535
216              and 0 respectively. Values outside this range are rounded up  or
217              down appropriately. Values other than zero cause a EDNS query to
218              be sent.
219
220       +[no]cdflag
221              This sets [or does not set] the CD (checking  disabled)  bit  in
222              the  query. This requests the server to not perform DNSSEC vali‐
223              dation of responses.
224
225       +[no]cookie=####
226              This sends [or does not send] a COOKIE EDNS option, with an  op‐
227              tional value. Replaying a COOKIE from a previous response allows
228              the server to identify a previous client. The  default  is  +no‐
229              cookie.
230
231       +[no]dnssec
232              This  requests that DNSSEC records be sent by setting the DNSSEC
233              OK (DO) bit in the OPT record in the additional section  of  the
234              query.
235
236       +[no]edns[=#]
237              This  specifies  [or does not specify] the EDNS version to query
238              with. Valid values are 0  to  255.   Setting  the  EDNS  version
239              causes  an EDNS query to be sent.  +noedns clears the remembered
240              EDNS version. EDNS is set to 0 by default.
241
242       +[no]ednsflags[=#]
243              This sets the must-be-zero EDNS flag bits (Z bits) to the speci‐
244              fied  value.   Decimal,  hex,  and octal encodings are accepted.
245              Setting a named flag (e.g. DO) is silently ignored. By  default,
246              no Z bits are set.
247
248       +[no]ednsopt[=code[:value]]
249              This  specifies  [or  does not specify] an EDNS option with code
250              point code and an optional payload of  value  as  a  hexadecimal
251              string. +noednsopt clears the EDNS options to be sent.
252
253       +[no]expire
254              This toggles sending of an EDNS Expire option.
255
256       +[no]nsid
257              This  toggles  inclusion  of an EDNS name server ID request when
258              sending a query.
259
260       +[no]recurse
261              This toggles the setting of the RD (recursion  desired)  bit  in
262              the  query.   This  bit is set by default, which means mdig nor‐
263              mally sends recursive queries.
264
265       +retry=T
266              This sets the number of times to retry UDP queries to server  to
267              T  instead  of  the default, 2. Unlike +tries, this does not in‐
268              clude the initial query.
269
270       +[no]subnet=addr[/prefix-length]
271              This sends [or does not send] an EDNS Client Subnet option  with
272              the specified IP address or network prefix.
273
274       mdig +subnet=0.0.0.0/0, or simply mdig +subnet=0
275              This  sends  an  EDNS client-subnet option with an empty address
276              and a source prefix-length of zero,  which  signals  a  resolver
277              that  the client's address information must not be used when re‐
278              solving this query.
279
280       +timeout=T
281              This sets the timeout for a query  to  T  seconds.  The  default
282              timeout  is  5  seconds for UDP transport and 10 for TCP. An at‐
283              tempt to set T to less than 1 results in a query  timeout  of  1
284              second being applied.
285
286       +tries=T
287              This  sets the number of times to try UDP queries to server to T
288              instead of the default, 3. If T is less than or equal  to  zero,
289              the number of tries is silently rounded up to 1.
290
291       +udptimeout=T
292              This sets the timeout between UDP query retries to T.
293
294       +[no]unknownformat
295              This  prints  [or  does  not print] all RDATA in unknown RR-type
296              presentation format (see RFC 3597).  The  default  is  to  print
297              RDATA for known types in the type's presentation format.
298
299       +[no]yaml
300              This  toggles  printing of the responses in a detailed YAML for‐
301              mat.
302
303       +[no]zflag
304              This sets [or does not set] the last unassigned DNS header  flag
305              in a DNS query.  This flag is off by default.
306

SEE ALSO

308       dig(1), RFC 1035.
309

AUTHOR

311       Internet Systems Consortium
312
314       2021, Internet Systems Consortium
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3199.16.23-RH                                                             MDIG(1)
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