DIG(1)                                BIND9                               DIG(1)

       dig - DNS lookup utility

       dig [@server] [-b address] [-c class] [-f filename] [-k filename] [-m]
           [-p port#] [-q name] [-t type] [-v] [-x addr] [-y [hmac:]name:key]
           [-4] [-6] [name] [type] [class] [queryopt...]

       dig [-h]

       dig [global-queryopt...] [query...]

       dig (domain information groper) is a flexible tool for interrogating DNS
       name servers. It performs DNS lookups and displays the answers that are
       returned from the name server(s) that were queried. Most DNS
       administrators use dig to troubleshoot DNS problems because of its
       flexibility, ease of use and clarity of output. Other lookup tools tend
       to have less functionality than dig.

       Although dig is normally used with command-line arguments, it also has a
       batch mode of operation for reading lookup requests from a file. A brief
       summary of its command-line arguments and options is printed when the -h
       option is given. Unlike earlier versions, the BIND 9 implementation of
       dig allows multiple lookups to be issued from the command line.

       Unless it is told to query a specific name server, dig will try each of
       the servers listed in /etc/resolv.conf. If no usable server addresses are
       found, dig will send the query to the local host.

       When no command line arguments or options are given, dig will perform an
       NS query for "." (the root).

       It is possible to set per-user defaults for dig via ${HOME}/.digrc. This
       file is read and any options in it are applied before the command line

       The IN and CH class names overlap with the IN and CH top level domain
       names. Either use the -t and -c options to specify the type and class,
       use the -q the specify the domain name, or use "IN." and "CH." when
       looking up these top level domains.

       A typical invocation of dig looks like:

            dig @server name type


           is the name or IP address of the name server to query. This can be an
           IPv4 address in dotted-decimal notation or an IPv6 address in
           colon-delimited notation. When the supplied server argument is a
           hostname, dig resolves that name before querying that name server.

           If no server argument is provided, dig consults /etc/resolv.conf; if
           an address is found there, it queries the name server at that
           address. If either of the -4 or -6 options are in use, then only
           addresses for the corresponding transport will be tried. If no usable
           addresses are found, dig will send the query to the local host. The
           reply from the name server that responds is displayed.

           is the name of the resource record that is to be looked up.

           indicates what type of query is required — ANY, A, MX, SIG, etc.
           type can be any valid query type. If no type argument is supplied,
           dig will perform a lookup for an A record.

           Use IPv4 only.

           Use IPv6 only.

       -b address[#port]
           Set the source IP address of the query. The address must be a valid
           address on one of the host's network interfaces, or "" or
           "::". An optional port may be specified by appending "#<port>"

       -c class
           Set the query class. The default class is IN; other classes are HS
           for Hesiod records or CH for Chaosnet records.

       -f file
           Batch mode: dig reads a list of lookup requests to process from the
           given file. Each line in the file should be organized in the same way
           they would be presented as queries to dig using the command-line

           Do reverse IPv6 lookups using the obsolete RFC1886 IP6.INT domain,
           which is no longer in use. Obsolete bit string label queries
           (RFC2874) are not attempted.

       -k keyfile
           Sign queries using TSIG using a key read from the given file. Key
           files can be generated using tsig-keygen(8). When using TSIG
           authentication with dig, the name server that is queried needs to
           know the key and algorithm that is being used. In BIND, this is done
           by providing appropriate key and server statements in named.conf.

           Enable memory usage debugging.

       -p port
           Send the query to a non-standard port on the server, instead of the
           defaut port 53. This option would be used to test a name server that
           has been configured to listen for queries on a non-standard port

       -q name
           The domain name to query. This is useful to distinguish the name from
           other arguments.

       -t type
           The resource record type to query. It can be any valid query type
           which is supported in BIND 9. The default query type is "A", unless
           the -x option is supplied to indicate a reverse lookup. A zone
           transfer can be requested by specifying a type of AXFR. When an
           incremental zone transfer (IXFR) is required, set the type to ixfr=N.
           The incremental zone transfer will contain the changes made to the
           zone since the serial number in the zone's SOA record was N.

           Print the version number and exit.

       -x addr
           Simplified reverse lookups, for mapping addresses to names. The addr
           is an IPv4 address in dotted-decimal notation, or a colon-delimited
           IPv6 address. When the -x is used, there is no need to provide the
           name, class and type arguments.  dig automatically performs a lookup
           for a name like and sets the query type and
           class to PTR and IN respectively. IPv6 addresses are looked up using
           nibble format under the IP6.ARPA domain (but see also the -i option).

       -y [hmac:]keyname:secret
           Sign queries using TSIG with the given authentication key.  keyname
           is the name of the key, and secret is the base64 encoded shared
           secret.  hmac is the name of the key algorithm; valid choices are
           hmac-md5, hmac-sha1, hmac-sha224, hmac-sha256, hmac-sha384, or
           hmac-sha512. If hmac is not specified, the default is hmac-md5 or if
           MD5 was disabled hmac-sha256.

           NOTE: You should use the -k option and avoid the -y option, because
           with -y the shared secret is supplied as a command line argument in
           clear text. This may be visible in the output from ps(1) or in a
           history file maintained by the user's shell.

       The dig command does not use the host name and address resolution or the
       DNS query routing mechanisms used by other processes running on macOS.
       The results of name or address queries printed by dig may differ from
       those found by other processes that use the macOS native name and address
       resolution mechanisms.  The results of DNS queries may also differ from
       queries that use the macOS DNS routing library.

       dig provides a number of query options which affect the way in which
       lookups are made and the results displayed. Some of these set or reset
       flag bits in the query header, some determine which sections of the
       answer get printed, and others determine the timeout and retry

       Each query option is identified by a keyword preceded by a plus sign (+).
       Some keywords set or reset an option. These may be preceded by the string
       no to negate the meaning of that keyword. Other keywords assign values to
       options like the timeout interval. They have the form +keyword=value.
       Keywords may be abbreviated, provided the abbreviation is unambiguous;
       for example, +cd is equivalent to +cdflag. The query options are:

           A synonym for +[no]aaonly.

           Sets the "aa" flag in the query.

           Display [do not display] the additional section of a reply. The
           default is to display it.

           Set [do not set] the AD (authentic data) bit in the query. This
           requests the server to return whether all of the answer and authority
           sections have all been validated as secure according to the security
           policy of the server. AD=1 indicates that all records have been
           validated as secure and the answer is not from a OPT-OUT range. AD=0
           indicate that some part of the answer was insecure or not validated.
           This bit is set by default.

           Set or clear all display flags.

           Display [do not display] the answer section of a reply. The default
           is to display it.

           Display [do not display] the authority section of a reply. The
           default is to display it.

           Attempt to display the contents of messages which are malformed. The
           default is to not display malformed answers.

           Set the UDP message buffer size advertised using EDNS0 to B bytes.
           The maximum and minimum sizes of this buffer are 65535 and 0
           respectively. Values outside this range are rounded up or down
           appropriately. Values other than zero will cause a EDNS query to be

           Set [do not set] the CD (checking disabled) bit in the query. This
           requests the server to not perform DNSSEC validation of responses.

           Display [do not display] the CLASS when printing the record.

           Toggles the printing of the initial comment in the output identifying
           the version of dig and the query options that have been applied. This
           comment is printed by default.

           Toggle the display of comment lines in the output. The default is to
           print comments.

           Send an COOKIE EDNS option, containing an optional value. Replaying a
           COOKIE from a previous response will allow the server to identify a
           previous client. The default is +nocookie.

           +cookie is automatically set when +trace is in use, to better emulate
           the default queries from a nameserver.

           This option was formerly called +[no]sit (Server Identity Token). In
           BIND 9.10.0 through BIND 9.10.2, it sent the experimental option code
           65001. This was changed to option code 10 in BIND 9.10.3 when the DNS
           COOKIE option was allocated.

           The +[no]sit is now deprecated, but has been retained as a synonym
           for +[no]cookie for backward compatibility within the BIND 9.10

           Toggle the display of cryptographic fields in DNSSEC records. The
           contents of these field are unnecessary to debug most DNSSEC
           validation failures and removing them makes it easier to see the
           common failures. The default is to display the fields. When omitted
           they are replaced by the string "[omitted]" or in the DNSKEY case the
           key id is displayed as the replacement, e.g. "[ key id = value ]".

           Deprecated, treated as a synonym for +[no]search

           Requests DNSSEC records be sent by setting the DNSSEC OK bit (DO) in
           the OPT record in the additional section of the query.

           Set the search list to contain the single domain somename, as if
           specified in a domain directive in /etc/resolv.conf, and enable
           search list processing as if the +search option were given.

           Specify the EDNS version to query with. Valid values are 0 to 255.
           Setting the EDNS version will cause a EDNS query to be sent.  +noedns
           clears the remembered EDNS version. EDNS is set to 0 by default.

           Set the must-be-zero EDNS flags bits (Z bits) to the specified value.
           Decimal, hex and octal encodings are accepted. Setting a named flag
           (e.g. DO) will silently be ignored. By default, no Z bits are set.

           Enable / disable EDNS version negotiation. By default EDNS version
           negotiation is enabled.

           Specify EDNS option with code point code and optionally payload of
           value as a hexadecimal string.  code can be either an EDNS option
           name (for example, NSID or ECS), or an arbitrary numeric value.
           +noednsopt clears the EDNS options to be sent.

           Send an EDNS Expire option.

           Do not try the next server if you receive a SERVFAIL. The default is
           to not try the next server which is the reverse of normal stub
           resolver behavior.

           Show [or do not show] the IP address and port number that supplied
           the answer when the +short option is enabled. If short form answers
           are requested, the default is not to show the source address and port
           number of the server that provided the answer.

           Convert [do not convert] puny code on output. This requires IDN
           SUPPORT to have been enabled at compile time. The default is to
           convert output.

           Ignore truncation in UDP responses instead of retrying with TCP. By
           default, TCP retries are performed.

           Keep the TCP socket open between queries and reuse it rather than
           creating a new TCP socket for each lookup. The default is

           Print records like the SOA records in a verbose multi-line format
           with human-readable comments. The default is to print each record on
           a single line, to facilitate machine parsing of the dig output.

           Set the number of dots that have to appear in name to D for it to be
           considered absolute. The default value is that defined using the
           ndots statement in /etc/resolv.conf, or 1 if no ndots statement is
           present. Names with fewer dots are interpreted as relative names and
           will be searched for in the domains listed in the search or domain
           directive in /etc/resolv.conf if +search is set.

           Include an EDNS name server ID request when sending a query.

           When this option is set, dig attempts to find the authoritative name
           servers for the zone containing the name being looked up and display
           the SOA record that each name server has for the zone.

           Print only one (starting) SOA record when performing an AXFR. The
           default is to print both the starting and ending SOA records.

           Set [restore] the DNS message opcode to the specified value. The
           default value is QUERY (0).

           Print [do not print] the query as it is sent. By default, the query
           is not printed.

           Print [do not print] the question section of a query when an answer
           is returned. The default is to print the question section as a

           A synonym for +[no]recurse.

           Toggle the setting of the RD (recursion desired) bit in the query.
           This bit is set by default, which means dig normally sends recursive
           queries. Recursion is automatically disabled when the +nssearch or
           +trace query options are used.

           Sets the number of times to retry UDP queries to server to T instead
           of the default, 2. Unlike +tries, this does not include the initial

           Toggle the display of per-record comments in the output (for example,
           human-readable key information about DNSKEY records). The default is
           not to print record comments unless multiline mode is active.

           Use [do not use] the search list defined by the searchlist or domain
           directive in resolv.conf (if any). The search list is not used by

           'ndots' from resolv.conf (default 1) which may be overridden by
           +ndots determines if the name will be treated as relative or not and
           hence whether a search is eventually performed or not.

           Provide a terse answer. The default is to print the answer in a
           verbose form.

           Perform [do not perform] a search showing intermediate results.

           Chase DNSSEC signature chains. Requires dig be compiled with
           -DDIG_SIGCHASE. This feature is deprecated. Use delv instead.

           This option is a synonym for +[no]cookie.

           The +[no]sit is deprecated.

           Split long hex- or base64-formatted fields in resource records into
           chunks of W characters (where W is rounded up to the nearest multiple
           of 4).  +nosplit or +split=0 causes fields not to be split at all.
           The default is 56 characters, or 44 characters when multiline mode is

           This query option toggles the printing of statistics: when the query
           was made, the size of the reply and so on. The default behavior is to
           print the query statistics.

           Send (don't send) an EDNS Client Subnet option with the specified IP
           address or network prefix.

           dig +subnet=, or simply dig +subnet=0 for short, sends an
           EDNS CLIENT-SUBNET option with an empty address and a source
           prefix-length of zero, which signals a resolver that the client's
           address information must not be used when resolving this query.

           Use [do not use] TCP when querying name servers. The default behavior
           is to use UDP unless an ixfr=N query is requested, in which case the
           default is TCP. AXFR queries always use TCP.

           Sets the timeout for a query to T seconds. The default timeout is 5
           seconds. An attempt to set T to less than 1 will result in a query
           timeout of 1 second being applied.

           When chasing DNSSEC signature chains perform a top-down validation.
           Requires dig be compiled with -DDIG_SIGCHASE. This feature is
           deprecated. Use delv instead.

           Toggle tracing of the delegation path from the root name servers for
           the name being looked up. Tracing is disabled by default. When
           tracing is enabled, dig makes iterative queries to resolve the name
           being looked up. It will follow referrals from the root servers,
           showing the answer from each server that was used to resolve the

           If @server is also specified, it affects only the initial query for
           the root zone name servers.

           +dnssec is also set when +trace is set to better emulate the default
           queries from a nameserver.

           Sets the number of times to try UDP queries to server to T instead of
           the default, 3. If T is less than or equal to zero, the number of
           tries is silently rounded up to 1.

           Specifies a file containing trusted keys to be used with +sigchase.
           Each DNSKEY record must be on its own line.

           If not specified, dig will look for /etc/trusted-key.key then
           trusted-key.key in the current directory.

           Requires dig be compiled with -DDIG_SIGCHASE. This feature is
           deprecated. Use delv instead.

           Display [do not display] the TTL when printing the record.

           Use [do not use] TCP when querying name servers. This alternate
           syntax to +[no]tcp is provided for backwards compatibility. The "vc"
           stands for "virtual circuit".

       The BIND 9 implementation of dig  supports specifying multiple queries on
       the command line (in addition to supporting the -f batch file option).
       Each of those queries can be supplied with its own set of flags, options
       and query options.

       In this case, each query argument represent an individual query in the
       command-line syntax described above. Each consists of any of the standard
       options and flags, the name to be looked up, an optional query type and
       class and any query options that should be applied to that query.

       A global set of query options, which should be applied to all queries,
       can also be supplied. These global query options must precede the first
       tuple of name, class, type, options, flags, and query options supplied on
       the command line. Any global query options (except the +[no]cmd option)
       can be overridden by a query-specific set of query options. For example:

           dig +qr www.isc.org any -x isc.org ns +noqr

       shows how dig could be used from the command line to make three lookups:
       an ANY query for www.isc.org, a reverse lookup of and a query
       for the NS records of isc.org. A global query option of +qr is applied,
       so that dig shows the initial query it made for each lookup. The final
       query has a local query option of +noqr which means that dig will not
       print the initial query when it looks up the NS records for isc.org.

       If dig has been built with IDN (internationalized domain name) support,
       it can accept and display non-ASCII domain names.  dig appropriately
       converts character encoding of domain name before sending a request to
       DNS server or displaying a reply from the server. If you'd like to turn
       off the IDN support for some reason, defines the IDN_DISABLE environment
       variable. The IDN support is disabled if the variable is set when dig



       delv(1), host(1), named(8), dnssec-keygen(8), RFC1035.

       There are probably too many query options.

       Internet Systems Consortium, Inc.

       Copyright © 2004-2011, 2013-2017 Internet Systems Consortium, Inc.
       Copyright © 2000-2003 Internet Software Consortium.

ISC                                2018-05-25                             DIG(1)