summaryrefslogtreecommitdiffstats
path: root/bin/dig/dig.rst
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--bin/dig/dig.rst809
1 files changed, 809 insertions, 0 deletions
diff --git a/bin/dig/dig.rst b/bin/dig/dig.rst
new file mode 100644
index 0000000..59ac9f1
--- /dev/null
+++ b/bin/dig/dig.rst
@@ -0,0 +1,809 @@
+.. Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+..
+.. SPDX-License-Identifier: MPL-2.0
+..
+.. This Source Code Form is subject to the terms of the Mozilla Public
+.. License, v. 2.0. If a copy of the MPL was not distributed with this
+.. file, you can obtain one at https://mozilla.org/MPL/2.0/.
+..
+.. See the COPYRIGHT file distributed with this work for additional
+.. information regarding copyright ownership.
+
+.. highlight: console
+
+.. iscman:: dig
+.. program:: dig
+.. _man_dig:
+
+dig - DNS lookup utility
+------------------------
+
+Synopsis
+~~~~~~~~
+:program:`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...]
+
+:program:`dig` [**-h**]
+
+:program:`dig` [global-queryopt...] [query...]
+
+Description
+~~~~~~~~~~~
+
+:program:`dig` 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 :program:`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 :program:`dig`.
+
+Although :program:`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 :option:`-h` option is given. The BIND 9
+implementation of :program:`dig` allows multiple lookups to be issued from the
+command line.
+
+Unless it is told to query a specific name server, :program:`dig` tries each
+of the servers listed in ``/etc/resolv.conf``. If no usable server
+addresses are found, :program:`dig` sends the query to the local host.
+
+When no command-line arguments or options are given, :program:`dig`
+performs an NS query for "." (the root).
+
+It is possible to set per-user defaults for :program:`dig` via
+``${HOME}/.digrc``. This file is read and any options in it are applied
+before the command-line arguments. The :option:`-r` option disables this
+feature, for scripts that need predictable behavior.
+
+The IN and CH class names overlap with the IN and CH top-level domain
+names. Either use the :option:`-t` and :option:`-c` options to specify the type and
+class, use the :option:`-q` to specify the domain name, or use "IN." and
+"CH." when looking up these top-level domains.
+
+Simple Usage
+~~~~~~~~~~~~
+
+A typical invocation of :program:`dig` looks like:
+
+::
+
+ dig @server name type
+
+where:
+
+.. option:: server
+
+ 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, :program:`dig` resolves that name before querying that name
+ server.
+
+ If no ``server`` argument is provided, :program:`dig` consults
+ ``/etc/resolv.conf``; if an address is found there, it queries the
+ name server at that address. If either of the :option:`-4` or :option:`-6`
+ options are in use, then only addresses for the corresponding
+ transport are tried. If no usable addresses are found, :program:`dig`
+ sends the query to the local host. The reply from the name server
+ that responds is displayed.
+
+.. option:: name
+
+ is the name of the resource record that is to be looked up.
+
+.. option:: type
+
+ 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, :program:`dig` performs a lookup for an A record.
+
+Options
+~~~~~~~
+
+.. option:: -4
+
+ This option indicates that only IPv4 should be used.
+
+.. option:: -6
+
+ This option indicates that only IPv6 should be used.
+
+.. option:: -b address[#port]
+
+ This option sets the source IP address of the query. The ``address`` must be a
+ valid address on one of the host's network interfaces, or "0.0.0.0"
+ or "::". An optional port may be specified by appending ``#port``.
+
+.. option:: -c class
+
+ This option sets the query class. The default ``class`` is IN; other classes are
+ HS for Hesiod records or CH for Chaosnet records.
+
+.. option:: -f file
+
+ This option sets batch mode, in which :program:`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 it would be presented as a query to :program:`dig` using the
+ command-line interface.
+
+.. option:: -h
+
+ Print a usage summary.
+
+.. option:: -k keyfile
+
+ This option tells :program:`dig` to sign queries using TSIG or
+ SIG(0) using a key read from the given file. Key files can be
+ generated using :iscman:`tsig-keygen`. When using TSIG authentication
+ with :program:`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 :iscman:`named.conf` for TSIG and by looking up the KEY record
+ in zone data for SIG(0).
+
+.. option:: -m
+
+ This option enables memory usage debugging.
+
+.. option:: -p port
+
+ This option sends the query to a non-standard port on the server, instead of the
+ default port 53. This option is used to test a name server that
+ has been configured to listen for queries on a non-standard port
+ number.
+
+.. option:: -q name
+
+ This option specifies the domain name to query. This is useful to distinguish the ``name``
+ from other arguments.
+
+.. option:: -r
+
+ This option indicates that options from ``${HOME}/.digrc`` should not be read. This is useful for
+ scripts that need predictable behavior.
+
+.. option:: -t type
+
+ This option indicates the resource record type to query, which can be any valid query type. If
+ it is a resource record type supported in BIND 9, it can be given by
+ the type mnemonic (such as ``NS`` or ``AAAA``). The default query type is
+ ``A``, unless the :option:`-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 contains
+ all changes made to the zone since the serial number in the zone's
+ SOA record was ``N``.
+
+ All resource record types can be expressed as ``TYPEnn``, where ``nn`` is
+ the number of the type. If the resource record type is not supported
+ in BIND 9, the result is displayed as described in :rfc:`3597`.
+
+.. option:: -u
+
+ This option indicates that print query times should be provided in microseconds instead of milliseconds.
+
+.. option:: -v
+
+ This option prints the version number and exits.
+
+.. option:: -x addr
+
+ This option sets 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 :option:`-x` option is used, there is no
+ need to provide the ``name``, ``class``, and ``type`` arguments.
+ :program:`dig` automatically performs a lookup for a name like
+ ``94.2.0.192.in-addr.arpa`` 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.
+
+.. option:: -y [hmac:]keyname:secret
+
+ This option signs 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``; if MD5 was disabled, the default is
+ ``hmac-sha256``.
+
+.. note:: Only the :option:`-k` option should be used, rather than the :option:`-y` option,
+ because with :option:`-y` the shared secret is supplied as a command-line
+ argument in clear text. This may be visible in the output from ``ps1`` or
+ in a history file maintained by the user's shell.
+
+Query Options
+~~~~~~~~~~~~~
+
+:program:`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
+strategies.
+
+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, :option:`+cd` is equivalent to
+:option:`+cdflag`. The query options are:
+
+.. option:: +aaflag, +noaaflag
+
+ This option is a synonym for :option:`+aaonly`, :option:`+noaaonly`.
+
+.. option:: +aaonly, +noaaonly
+
+ This option sets the ``aa`` flag in the query.
+
+.. option:: +additional, +noadditional
+
+ This option displays [or does not display] the additional section of a reply. The
+ default is to display it.
+
+.. option:: +adflag, +noadflag
+
+ This option sets [or does 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 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``
+ indicates that some part of the answer was insecure or not validated.
+ This bit is set by default.
+
+.. option:: +all, +noall
+
+ This option sets or clears all display flags.
+
+.. option:: +answer, +noanswer
+
+ This option displays [or does not display] the answer section of a reply. The default
+ is to display it.
+
+.. option:: +authority, +noauthority
+
+ This option displays [or does not display] the authority section of a reply. The
+ default is to display it.
+
+.. option:: +badcookie, +nobadcookie
+
+ This option retries the lookup with a new server cookie if a BADCOOKIE response is
+ received.
+
+.. option:: +besteffort, +nobesteffort
+
+ This option attempts to display the contents of messages which are malformed. The
+ default is to not display malformed answers.
+
+.. option:: +bufsize[=B]
+
+ This option sets the UDP message buffer size advertised using EDNS0 to
+ ``B`` bytes. The maximum and minimum sizes of this buffer are 65535 and
+ 0, respectively. ``+bufsize`` restores the default buffer size.
+
+.. option:: +cd, +cdflag, +nocdflag
+
+ This option sets [or does not set] the CD (checking disabled) bit in the query. This
+ requests the server to not perform DNSSEC validation of responses.
+
+.. option:: +class, +noclass
+
+ This option displays [or does not display] the CLASS when printing the record.
+
+.. option:: +cmd, +nocmd
+
+ This option toggles the printing of the initial comment in the output, identifying the
+ version of :program:`dig` and the query options that have been applied. This option
+ always has a global effect; it cannot be set globally and then overridden on a
+ per-lookup basis. The default is to print this comment.
+
+.. option:: +comments, +nocomments
+
+ This option toggles the display of some comment lines in the output, with
+ information about the packet header and OPT pseudosection, and the names of
+ the response section. The default is to print these comments.
+
+ Other types of comments in the output are not affected by this option, but
+ can be controlled using other command-line switches. These include
+ :option:`+cmd`, :option:`+question`, :option:`+stats`, and :option:`+rrcomments`.
+
+.. option:: +cookie=####, +nocookie
+
+ This option sends [or does not send] a COOKIE EDNS option, with an optional value. Replaying a COOKIE
+ from a previous response allows the server to identify a previous
+ client. The default is ``+cookie``.
+
+ ``+cookie`` is also set when :option:`+trace` is set to better emulate the
+ default queries from a nameserver.
+
+.. option:: +crypto, +nocrypto
+
+ This option toggles the display of cryptographic fields in DNSSEC records. The
+ contents of these fields are unnecessary for debugging 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 ]``.
+
+.. option:: +defname, +nodefname
+
+ This option, which is deprecated, is treated as a synonym for
+ :option:`+search`, :option:`+nosearch`.
+
+.. option:: +dns64prefix, +nodns64prefix
+
+ Lookup IPV4ONLY.ARPA AAAA and print any DNS64 prefixes found.
+
+.. option:: +dnssec, +do, +nodnssec, +nodo
+
+ This option requests that DNSSEC records be sent by setting the DNSSEC OK (DO) bit in
+ the OPT record in the additional section of the query.
+
+.. option:: +domain=somename
+
+ This option sets the search list to contain the single domain ``somename``, as if
+ specified in a ``domain`` directive in ``/etc/resolv.conf``, and
+ enables search list processing as if the :option:`+search` option were
+ given.
+
+.. option:: +dscp=value
+
+ This option formerly set the DSCP value used when sending a query.
+ It is now obsolete, and has no effect.
+
+.. option:: +edns[=#], +noedns
+
+ This option specifies the EDNS version to query with. Valid values are 0 to 255.
+ Setting the EDNS version causes an EDNS query to be sent.
+ ``+noedns`` clears the remembered EDNS version. EDNS is set to 0 by
+ default.
+
+.. option:: +ednsflags[=#], +noednsflags
+
+ This option sets 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) is silently ignored. By default, no Z bits are set.
+
+.. option:: +ednsnegotiation, +noednsnegotiation
+
+ This option enables/disables EDNS version negotiation. By default, EDNS version
+ negotiation is enabled.
+
+.. option:: +ednsopt[=code[:value]], +noednsopt
+
+ This option specifies the EDNS option with code point ``code`` and an optional 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.
+
+.. option:: +expire, +noexpire
+
+ This option sends an EDNS Expire option.
+
+.. option:: +fail, +nofail
+
+ This option indicates that :iscman:`named` should try [or not try] the next server if a SERVFAIL is received. The default is
+ to not try the next server, which is the reverse of normal stub
+ resolver behavior.
+
+.. option:: +fuzztime[=value], +nofuzztime
+
+ This option allows the signing time to be specified when generating
+ signed messages. If a value is specified it is the seconds since
+ 00:00:00 January 1, 1970 UTC ignoring leap seconds. If no value
+ is specified 1646972129 (Fri 11 Mar 2022 04:15:29 UTC) is used.
+ The default is ``+nofuzztime`` and the current time is used.
+
+.. option:: +header-only, +noheader-only
+
+ This option sends a query with a DNS header without a question section. The
+ default is to add a question section. The query type and query name
+ are ignored when this is set.
+
+.. option:: +https[=value], +nohttps
+
+ This option indicates whether to use DNS over HTTPS (DoH) when querying
+ name servers. When this option is in use, the port number defaults to 443.
+ The HTTP POST request mode is used when sending the query.
+
+ If ``value`` is specified, it will be used as the HTTP endpoint in the
+ query URI; the default is ``/dns-query``. So, for example, ``dig
+ @example.com +https`` will use the URI ``https://example.com/dns-query``.
+
+.. option:: +https-get[=value], +nohttps-get
+
+ Similar to :option:`+https`, except that the HTTP GET request mode is used
+ when sending the query.
+
+.. option:: +https-post[=value], +nohttps-post
+
+ Same as :option:`+https`.
+
+.. option:: +http-plain[=value], +nohttp-plain
+
+ Similar to :option:`+https`, except that HTTP queries will be sent over a
+ non-encrypted channel. When this option is in use, the port number
+ defaults to 80 and the HTTP request mode is POST.
+
+.. option:: +http-plain-get[=value], +nohttp-plain-get
+
+ Similar to :option:`+http-plain`, except that the HTTP request mode is GET.
+
+.. option:: +http-plain-post[=value], +nohttp-plain-post
+
+ Same as :option:`+http-plain`.
+
+.. option:: +identify, +noidentify
+
+ This option shows [or does not show] the IP address and port number that
+ supplied the answer, when the :option:`+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.
+
+.. option:: +idnin, +noidnin
+
+ This option processes [or does not process] IDN domain names on input. This requires
+ ``IDN SUPPORT`` to have been enabled at compile time.
+
+ The default is to process IDN input when standard output is a tty.
+ The IDN processing on input is disabled when :program:`dig` output is redirected
+ to files, pipes, and other non-tty file descriptors.
+
+.. option:: +idnout, +noidnout
+
+ This option converts [or does not convert] puny code on output. This requires
+ ``IDN SUPPORT`` to have been enabled at compile time.
+
+ The default is to process puny code on output when standard output is
+ a tty. The puny code processing on output is disabled when :program:`dig` output
+ is redirected to files, pipes, and other non-tty file descriptors.
+
+.. option:: +ignore, +noignore
+
+ This option ignores [or does not ignore] truncation in UDP responses instead of retrying with TCP. By
+ default, TCP retries are performed.
+
+.. option:: +keepalive, +nokeepalive
+
+ This option sends [or does not send] an EDNS Keepalive option.
+
+.. option:: +keepopen, +nokeepopen
+
+ This option keeps [or does not keep] the TCP socket open between queries, and reuses it rather than
+ creating a new TCP socket for each lookup. The default is
+ ``+nokeepopen``.
+
+.. option:: +multiline, +nomultiline
+
+ This option prints [or does not 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 :program:`dig` output.
+
+.. option:: +ndots=D
+
+ This option sets the number of dots (``D``) that must appear in ``name`` 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 are searched for in the domains listed in the
+ ``search`` or ``domain`` directive in ``/etc/resolv.conf`` if
+ :option:`+search` is set.
+
+.. option:: +nsid, +nonsid
+
+ When enabled, this option includes an EDNS name server ID request when sending a query.
+
+.. option:: +nssearch, +nonssearch
+
+ When this option is set, :program:`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.
+ Addresses of servers that did not respond are also printed.
+
+.. option:: +onesoa, +noonesoa
+
+ When enabled, this option prints only one (starting) SOA record when performing an AXFR. The
+ default is to print both the starting and ending SOA records.
+
+.. option:: +opcode=value, +noopcode
+
+ When enabled, this option sets (restores) the DNS message opcode to the specified value. The
+ default value is QUERY (0).
+
+.. option:: +padding=value
+
+ This option pads the size of the query packet using the EDNS Padding option to
+ blocks of ``value`` bytes. For example, ``+padding=32`` causes a
+ 48-byte query to be padded to 64 bytes. The default block size is 0,
+ which disables padding; the maximum is 512. Values are ordinarily
+ expected to be powers of two, such as 128; however, this is not
+ mandatory. Responses to padded queries may also be padded, but only
+ if the query uses TCP or DNS COOKIE.
+
+.. option:: +qid=value
+
+ This option specifies the query ID to use when sending queries.
+
+.. option:: +qr, +noqr
+
+ This option toggles the display of the query message as it is sent. By default, the query
+ is not printed.
+
+.. option:: +question, +noquestion
+
+ This option toggles the display of the question section of a query when an answer is
+ returned. The default is to print the question section as a comment.
+
+.. option:: +raflag, +noraflag
+
+ This option sets [or does not set] the RA (Recursion Available) bit in the query. The
+ default is ``+noraflag``. This bit is ignored by the server for
+ QUERY.
+
+.. option:: +rdflag, +nordflag
+
+ This option is a synonym for :option:`+recurse`, :option:`+norecurse`.
+
+.. option:: +recurse, +norecurse
+
+ This option toggles the setting of the RD (recursion desired) bit in the query.
+ This bit is set by default, which means :program:`dig` normally sends
+ recursive queries. Recursion is automatically disabled when the
+ :option:`+nssearch` or :option:`+trace` query option is used.
+
+.. option:: +retry=T
+
+ This option sets the number of times to retry UDP and TCP queries to server to ``T``
+ instead of the default, 2. Unlike :option:`+tries`, this does not include
+ the initial query.
+
+.. option:: +rrcomments, +norrcomments
+
+ This option toggles 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.
+
+.. option:: +search, +nosearch
+
+ This option uses [or does not use] the search list defined by the searchlist or domain
+ directive in ``resolv.conf``, if any. The search list is not used by
+ default.
+
+ ``ndots`` from ``resolv.conf`` (default 1), which may be overridden by
+ :option:`+ndots`, determines whether the name is treated as relative
+ and hence whether a search is eventually performed.
+
+.. option:: +short, +noshort
+
+ This option toggles whether a terse answer is provided. The default is to print the answer in a verbose
+ form. This option always has a global effect; it cannot be set globally and
+ then overridden on a per-lookup basis.
+
+.. option:: +showbadcookie, +noshowbadcookie
+
+ This option toggles whether to show the message containing the
+ BADCOOKIE rcode before retrying the request or not. The default
+ is to not show the messages.
+
+.. option:: +showsearch, +noshowsearch
+
+ This option performs [or does not perform] a search showing intermediate results.
+
+.. option:: +sigchase, +nosigchase
+
+ This feature is now obsolete and has been removed; use :iscman:`delv`
+ instead.
+
+.. option:: +split=W
+
+ This option splits 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 active.
+
+.. option:: +stats, +nostats
+
+ This option toggles the printing of statistics: when the query was made, the size of the
+ reply, etc. The default behavior is to print the query statistics as a
+ comment after each lookup.
+
+.. option:: +subnet=addr[/prefix-length], +nosubnet
+
+ This option sends [or does not send] an EDNS CLIENT-SUBNET option with the specified IP
+ address or network prefix.
+
+ ``dig +subnet=0.0.0.0/0``, 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.
+
+.. option:: +tcflag, +notcflag
+
+ This option sets [or does not set] the TC (TrunCation) bit in the query. The default is
+ ``+notcflag``. This bit is ignored by the server for QUERY.
+
+.. option:: +tcp, +notcp
+
+ This option indicates whether to use TCP when querying name
+ servers. The default behavior is to use UDP unless a type ``any``
+ or ``ixfr=N`` query is requested, in which case the default is
+ TCP. AXFR queries always use TCP. To prevent retry over TCP when
+ TC=1 is returned from a UDP query, use ``+ignore``.
+
+.. option:: +timeout=T
+
+ This option sets the timeout for a query to ``T`` seconds. The default timeout is
+ 5 seconds. An attempt to set ``T`` to less than 1 is silently set to 1.
+
+.. option:: +tls, +notls
+
+ This option indicates whether to use DNS over TLS (DoT) when querying
+ name servers. When this option is in use, the port number defaults
+ to 853.
+
+.. option:: +tls-ca[=file-name], +notls-ca
+
+ This option enables remote server TLS certificate validation for
+ DNS transports, relying on TLS. Certificate authorities
+ certificates are loaded from the specified PEM file
+ (``file-name``). If the file is not specified, the default
+ certificates from the global certificates store are used.
+
+.. option:: +tls-certfile=file-name, +tls-keyfile=file-name, +notls-certfile, +notls-keyfile
+
+ These options set the state of certificate-based client
+ authentication for DNS transports, relying on TLS. Both certificate
+ chain file and private key file are expected to be in PEM format.
+ Both options must be specified at the same time.
+
+.. option:: +tls-hostname=hostname, +notls-hostname
+
+ This option makes :program:`dig` use the provided hostname during remote
+ server TLS certificate verification. Otherwise, the DNS server name
+ is used. This option has no effect if :option:`+tls-ca` is not specified.
+
+.. option:: +topdown, +notopdown
+
+ This feature is related to :option:`dig +sigchase`, which is obsolete and
+ has been removed. Use :iscman:`delv` instead.
+
+.. option:: +trace, +notrace
+
+ This option toggles 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, :program:`dig` makes iterative queries to resolve the
+ name being looked up. It follows referrals from the root servers,
+ showing the answer from each server that was used to resolve the
+ lookup.
+
+ If ``@server`` is also specified, it affects only the initial query for
+ the root zone name servers.
+
+ :option:`+dnssec` is also set when :option:`+trace` is set, to better emulate the
+ default queries from a name server.
+
+.. option:: +tries=T
+
+ This option sets the number of times to try UDP and TCP 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.
+
+.. option:: +trusted-key=####
+
+ This option formerly specified trusted keys for use with :option:`dig +sigchase`. This
+ feature is now obsolete and has been removed; use :iscman:`delv` instead.
+
+.. option:: +ttlid, +nottlid
+
+ This option displays [or does not display] the TTL when printing the record.
+
+.. option:: +ttlunits, +nottlunits
+
+ This option displays [or does not display] the TTL in friendly human-readable time
+ units of ``s``, ``m``, ``h``, ``d``, and ``w``, representing seconds, minutes,
+ hours, days, and weeks. This implies :option:`+ttlid`.
+
+.. option:: +unknownformat, +nounknownformat
+
+ This option prints all RDATA in unknown RR type presentation format (:rfc:`3597`).
+ The default is to print RDATA for known types in the type's
+ presentation format.
+
+.. option:: +vc, +novc
+
+ This option uses [or does not use] TCP when querying name servers. This alternate
+ syntax to :option:`+tcp` is provided for backwards compatibility. The
+ ``vc`` stands for "virtual circuit."
+
+.. option:: +yaml, +noyaml
+
+ When enabled, this option prints the responses (and, if :option:`+qr` is in use, also the
+ outgoing queries) in a detailed YAML format.
+
+.. option:: +zflag, +nozflag
+
+ This option sets [or does not set] the last unassigned DNS header flag in a DNS query.
+ This flag is off by default.
+
+Multiple Queries
+~~~~~~~~~~~~~~~~
+
+The BIND 9 implementation of :program:`dig` supports specifying multiple
+queries on the command line (in addition to supporting the :option:`-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 represents 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 :option:`+cmd` and
+:option:`+short` options) can be overridden by a query-specific set of
+query options. For example:
+
+::
+
+ dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr
+
+shows how :program:`dig` can be used from the command line to make three
+lookups: an ANY query for ``www.isc.org``, a reverse lookup of 127.0.0.1,
+and a query for the NS records of ``isc.org``. A global query option of
+:option:`+qr` is applied, so that :program:`dig` shows the initial query it made for
+each lookup. The final query has a local query option of :option:`+noqr` which
+means that :program:`dig` does not print the initial query when it looks up the
+NS records for ``isc.org``.
+
+IDN Support
+~~~~~~~~~~~
+
+If :program:`dig` has been built with IDN (internationalized domain name)
+support, it can accept and display non-ASCII domain names. :program:`dig`
+appropriately converts character encoding of a domain name before sending
+a request to a DNS server or displaying a reply from the server.
+To turn off IDN support, use the parameters
+:option:`+idnin` and :option:`+idnout`, or define the ``IDN_DISABLE`` environment
+variable.
+
+Return Codes
+~~~~~~~~~~~~
+
+:program:`dig` return codes are:
+
+``0``
+ DNS response received, including NXDOMAIN status
+
+``1``
+ Usage error
+
+``8``
+ Couldn't open batch file
+
+``9``
+ No reply from server
+
+``10``
+ Internal error
+
+Files
+~~~~~
+
+``/etc/resolv.conf``
+
+``${HOME}/.digrc``
+
+See Also
+~~~~~~~~
+
+:iscman:`delv(1) <delv>`, :iscman:`host(1) <host>`, :iscman:`named(8) <named>`, :iscman:`dnssec-keygen(8) <dnssec-keygen>`, :rfc:`1035`.
+
+Bugs
+~~~~
+
+There are probably too many query options.