My favorite query: dig domainname.com ANY +noall +answer

DIG(1) BIND9 DIG(1)

NAME
dig – DNS lookup utility

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

dig [-h]

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

DESCRIPTION
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.

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 arguments.

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

SIMPLE USAGE
A typical invocation of dig looks like:

dig @server name type

where:

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, dig resolves that name before querying that name server.
If no server argument is provided, dig consults /etc/resolv.conf
and queries the name servers listed there. The reply from the name
server that responds is displayed.

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

type
indicates what type of query is required â 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. Continue reading →