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 DIG(1)                                                               DIG(1)
                               August 30, 1990



 NAME
      dig - send domain name query packets to name servers

 SYNOPSIS
      dig [@server] domain [<query-type>] [<query-class>] [+<query-option>]
      [-<dig-option>] [%comment]

 DESCRIPTION
      Dig (domain information groper) is a flexible command line tool which
      can be used to gather information from the Domain Name System servers.
      Dig has two modes: simple interactive mode which makes a single query,
      and batch which executes a query for each in a list of several query
      lines. All query options are accessible from the command line.

      The usual simple use of dig will take the form:

           dig  @server  domain   query-type  query-class

      where:

      server
           may be either a domain name or a dot-notation Internet address.
           If this optional field is omitted, dig will attempt to use the
           default name server for your machine.

           Note: If a domain name is specified, this will be resolved using
           the domain name system resolver (i.e., BIND). If your system does
           not support DNS,  you may have to specify a dot-notation address.
           Alternatively, if there is a server at your disposal somewhere,
           all that is required is that /etc/resolv.conf be present and
           indicate where the default name servers  reside,  so that  server
           itself can be resolved. See resolver(5) for information on
           /etc/resolv.conf.  (WARNING: Changing /etc/resolv.conf will
           affect the standard  resolver library and  potentially several
           programs which use it.) As an option, the user may set the
           environment variable LOCALRES to name a file which is to be used
           instead of /etc/resolv.conf (LOCALRES is specific to the dig
           resolver and  not referenced by the standard resolver). If the
           LOCALRES variable is not set or the file is not readable then
           /etc/resolv.conf will be used.

      domain
           is the domain name for which you are requesting information.  See
           OPTIONS [-x] for convenient way to specify inverse address query.

      query-type
           is the type of information (DNS query type) that you are
           requesting. If omitted, the default is "a" (T_A = address).  The
           following types are recognized:

           a      T_A      network address



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 DIG(1)                                                               DIG(1)
                               August 30, 1990



           any    T_ANY    all/any information about specified domain
           mx     T_MX     mail exchanger for the domain
           ns     T_NS     name servers
           soa    T_SOA    zone of authority record
           hinfo  T_HINFO  host information
           axfr   T_AXFR   zone transfer
                            (must ask an authoritative server)
           txt    T_TXT    arbitrary number of strings
                            (not yet supported by BIND)

           (See RFC 1035 for the complete list.)

      query-class
           is the network class requested in the query. If omitted, the
           default is "in" (C_IN = Internet).  The following classes are
           recognized:

           in     C_IN     Internet class domain
           any    C_ANY    all/any class information

           (See RFC 1035 for the complete list.)

           Note: "Any" can be used to specify a class and/or a type of
           query. Dig will parse the first occurrence of "any" to mean
           query-type = T_ANY. To specify query-class = C_ANY you must
           either specify "any" twice, or set query-class using "-c" option
           (see below).

 OTHER OPTIONS
      %ignored-comment
           "%" is used to included an argument that is simply not parsed.
           This may be useful  if running dig in batch mode. Instead of
           resolving every @server-domain-name in a list of queries, you can
           avoid the overhead of doing so, and still have the domain name on
           the command line as a reference. Example:

                  dig  @128.9.0.32  %venera.isi.edu  mx  isi.edu


      -<dig option>
           "-" is used to specify an option which effects the operation of
           dig. The following options are currently available (although not
           guaranteed to be useful):

           -x dot-notation-address
                Convenient form to specify inverse address mapping.  Instead
                of "dig 32.0.9.128.in-addr.arpa" one can simply "dig -x
                128.9.0.32".

           -f file
                File for dig batch mode. The file contains a list of query



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 DIG(1)                                                               DIG(1)
                               August 30, 1990



                specifications (dig command lines) which are to be executed
                successively. Lines beginning with ';', '#', or '\n' are
                ignored. Other options may still appear on command line, and
                will be in effect for each batch query.

           -T time
                Time in seconds between start of successive queries when
                running in batch mode. Can be used to keep two or more batch
                dig commands running roughly in sync. Default is zero.

           -p port
                Port number. Query a name server listening to a non-standard
                port number. Default is 53.

           -P[ping-string]
                After query returns, execute a ping(8) command for response
                time comparison. This rather unelegantly makes a call to the
                shell. The last three lines of statistics is printed for the
                command:

                       ping -s server_name 56 3

                If the optional "ping string" is present, it replaces "ping
                -s" in the shell command.

           -t query-type
                Specify type of query. May specify either an integer value
                to be included in the type field or use the abbreviated
                mnemonic as discussed above (i.e., mx  = T_MX).

           -c query-class
                Specify class of query. May specify either an integer value
                to be included in the class field or use the abbreviated
                mnemonic as discussed above (i.e., in = C_IN).

           -envsav
                This flag specifies that the dig environment (defaults,
                print options, etc.), after all of the arguments are parsed,
                should be saved to a file to become the default environment.
                Useful if you do not like the standard set of defaults and
                do not desire to include a large number of options each time
                dig is used.  The environment consists of resolver state
                variable flags, timeout, and retries as well as the flags
                detailing dig output (see below).  If the shell environment
                variable LOCALDEF is set to the name of a file, this is
                where the default dig environment is saved. If not, the file
                "DiG.env" is created in the current working directory.

                Note: LOCALDEF is specific to the dig resolver, and will not
                affect operation of the standard resolver library.




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 DIG(1)                                                               DIG(1)
                               August 30, 1990



                Each time dig is executed, it looks for "./DiG.env" or the
                file specified by the shell environment variable LOCALDEF.
                If such file exists and is readable, then the environment is
                restored from this file before any arguments are parsed.

           -envset
                This flag only affects batch query runs. When "-envset" is
                specified on a line in a dig batch file, the dig environment
                after the arguments are parsed, becomes the default
                environment for the duration of the batch file, or until the
                next line which specifies "-envset".

           -[no]stick
                This flag only affects batch query runs.  It specifies that
                the dig environment (as read initially or set by "-envset"
                switch) is to be restored before each query (line) in a dig
                batch file.  The default "-nostick" means that the dig
                environment does not stick, hence options specified on a
                single line in a dig batch file will remain in effect for
                subsequent lines (i.e. they are not restored to the "sticky"
                default).


      +<query option>
           "+" is used to specify an option to be changed in the query
           packet or to change dig output specifics. Many of these are the
           same parameters accepted by nslookup(1).  If an option requires a
           parameter, the form is as follows:

                  +keyword[=value]

           Most keywords can be abbreviated.  Parsing of the "+" options  is
           very  simplistic - a value must not be separated from its keyword
           by white space. The following keywords are currently available:

           Keyword      Abbrev. Meaning [default]

           [no]debug    (deb)   turn on/off debugging mode [deb]
           [no]d2               turn on/off extra debugging mode [nod2]
           [no]recurse  (rec)   use/don't use recursive lookup [rec]
           retry=#      (ret)   set number of retries to # [4]
           time=#       (ti)    set timeout length to # seconds [4]
           [no]ko               keep open option (implies vc) [noko]
           [no]vc               use/don't use virtual circuit [novc]
           [no]defname  (def)   use/don't use default domain name [def]
           [no]search   (sea)   use/don't use domain search list [sea]
           domain=NAME  (do)    set default domain name to NAME
           [no]ignore   (i)     ignore/don't ignore trunc. errors [noi]
           [no]primary  (pr)     use/don't use primary server [nopr]
           [no]aaonly   (aa)    authoritative query only flag [noaa]
           [no]sort     (sor)   sort resource records [nosor]



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 DIG(1)                                                               DIG(1)
                               August 30, 1990



           [no]cmd              echo parsed arguments [cmd]
           [no]stats    (st)    print query statistics (RTT,etc) [st]
           [no]Header   (H)     print basic header [H]
           [no]header   (he)    print header flags [he]
           [no]ttlid    (tt)    print TTLs [tt]
           [no]cl               print class info [nocl]
           [no]qr               print outgoing query [noqr]
           [no]reply    (rep)   print reply [rep]
           [no]ques     (qu)    print question section [qu]
           [no]answer   (an)    print answer section [an]
           [no]author   (au)    print authoritative section [au]
           [no]addit    (ad)    print additional section [ad]
           pfdef                set to default print flags
           pfmin                set to minimal default print flags
           pfset=#              set print flags to #
                                (# can be hex/octal/decimal)
           pfand=#              bitwise and print flags with #
           pfor=#               bitwise or print flags with #

           The retry and time options affect the retransmission strategy
           used by resolver library when sending datagram queries. The
           algorithm is as follows:

                for i = 0 to retry - 1
                    for j = 1 to num_servers
                             send_query
                             wait((time * (2**i)) / num_servers)
                    end
                end

           (Note: dig always uses a value of 1 for num_servers.)

           Pfset, pfand, and pfor were included to make manipulation of the
           various print options less tedious. Below are the currently
           defined meanings for the various print flag bits.  They may be
           combined (ANDed) to achieve various output formats.

           PRF_STATS  0x0001  RTT, query & server host, date, msg size
           PRF_CLASS  0x0004  Resource record class information
           PRF_CMD    0x0008  dig command line echo
           PRF_QUES   0x0010  questions section
           PRF_ANS    0x0020  answers section
           PRF_AUTH   0x0040  authoritative section
           PRF_ADD    0x0080  additional records section
           PRF_HEAD1  0x0100  RR section headers & counts
           PRF_HEAD2  0x0200  pkt header flags
           PRF_TTLID  0x0400  Resource record ttl
           PRF_HEADX  0x0800  basic header
           PRF_QUERY  0x1000  outgoing query packet
           PRF_REPLY  0x2000  reply packet
           PRF_SORT   0x8000  sort various response sections



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 DIG(1)                                                               DIG(1)
                               August 30, 1990



           PRF_DEF    0x2ff9  default dig settings
           PRF_ZONE   0x24f9  default setting for zone transfer
           PRF_MIN    0xa930  minimalistic dig settings for
                              (future) automated server testing

           When setting the print options, if you want to see information
           other than statistics, you should choose to examine the outgoing
           (0x1000), incoming (0x2000), or both packets plus the specific
           sections of the packet you are interested in.

 DETAILS
      Dig requires a slightly modified version of the BIND resolver(3)
      library to gather count and time statistics. Otherwise, it is
      straight-forward (albeit not pretty) effort of parsing arguments and
      setting appropriate parameters. Dig uses resolver routines res_init(),
      res_mkquery(), res_send() as well as accessing _res structure.
      Compiling dig with the standard resolver library is possible, but will
      change the output format, make the print options meaningless, and not
      gather RTT and packet count stats.

 FILES
      /etc/resolv.conf  initial domain name and name server
                        addresses

 ENVIRONMENT
      LOCALRES          file to use in place of /etc/resolv.conf
      LOCALDEF          default environment file

 AUTHOR
      Steve Hotz hotz@isi.edu

 ACKNOWLEDGMENTS
      Dig uses functions from nslookup(1) authored by Andrew Cherenson;
      taken from Berkeley BIND 4.8 distribution. The resolver library is
      primarily from the Berkeley 4.8 BIND distribution.

 BUGS
      Dig has a serious case of "creeping featurism" -- the result of
      considering several potential uses during it's development.  It would
      probably benefit from a rigorous diet.  Similarly, the print flags and
      granularity of the items they specify make evident their rather ad hoc
      genesis.

      Dig does not consistently exit nicely (with appropriate status) when a
      problem occurs somewhere in the resolver (NOTE: most of the common
      exit cases are handled).  This is particularly annoying when running
      in batch mode.  If it exits abnormally (and is not caught), the entire
      batch aborts; when such an event is trapped, dig simply continues with
      the next query.





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 DIG(1)                                                               DIG(1)
                               August 30, 1990



 SEE ALSO
      named(8),  resolver(3),  resolver(5),  nslookup(1)




















































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