dig(1M)
NAME
dig - send domain name query packets to name servers
SYNOPSIS
dig [@server] domain [query-type] [query-class] [+query-
option] [-dig-option] [%ignored-comment]
DESCRIPTION
Use dig ("domain information groper") to gather information
from the Domain Name System ("DNS") servers. dig has two
modes, simple interactive mode for a single query, and
batch mode, which executes a query for each line in a list
of several query lines. All query options are accessible
from the command line.
OPTIONS
The dig utility supports the following options:
@server
Either a domain name or a raw IPV4 or IPv6 Inter-
net address. If this field is omitted, dig
attempts to use the default name server for the
machine. If a domain name is specified, this will be
resolved using the domain name system resolver,
for example, BIND. If the system does not support
DNS, specify a literal IPv4 or IPv6 address. Alter-
natively, /etc/resolv.conf should be present. It
indicates where the default name servers reside, so
that server itself can be resolved. See
resolver(3RESOLV) for information on
/etc/resolv.conf. As an option, set the environment
variable LOCALRES to name a file which is to be used
instead of the /etc/resolv.conf standard resolver.
LOCALRES is specific to the dig resolver and is
not referenced by the system resolver. If the
LOCALRES variable is not set or the specified file
is not readable, then /etc/resolv.conf will be used.
-domain
The domain name for which you are requesting infor-
mation. See the -x option for a convenient way to
specify an inverse address query.
query-type
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
any T_ANY any and all 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
See RFC 1035 for a complete list of values for query-
type.
query-class
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 any and all class information
See RFC 1035 for a complete list of values for query-
class.
any can be used to specify a class and a type of
query. dig parses the first occurrence of any to
mean query-type=T_ANY. To specify query-class=C_ANY,
either specify any twice, or set query-class using
the -c option.
%ignored-comment
``%'' is used to include an argument that is not
parsed. This is useful when running dig in batch
mode. For example:
example% dig @128.9.0.32 %venera.isi.edu mx isi.edu
-dig option
``-'' is used to specify an option that affects the
operation of dig. The following options are currently
available:
-x dot-notation-address
Specify inverse address mapping. Instead of:
example% dig 32.0.9.128.in-addr.arpa
Specify:
example% dig -x 128.9.0.32
-x IPv6-address
Specify inverse address maping. Instead of:
example% dig 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0. \
0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa
Specify:
example% dig -x ::1
-f file
Batch mode. file contains a list of query
specifications, that is, dig command lines,
which are to be executed successively. Lines
that begin with `;', `#', or `0' are ignored.
Other options may still appear on command line
that will be in effect for each batch query.
-T time
Specify the time in seconds between the start of
successive queries in batch mode. This option
can be used synchronize two or more batch dig
commands. The default is zero.
-p port
Specify port number. This option allows you to
query a name server that listens to a non-
standard port number. The default is 53.
-P [ping-string]
After query returns, execute a ping(1M) command
for response time comparison. This option makes
a call to the shell. The last three ,lines of
statistics are printed for the command:
example % 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. You may specify either
an integer value to be included in the type
field, or use the abbreviated mnemonic. for
example, mx = T_MX.
-c query-class
Specify class of query. You may specify either
an integer value to be included in the class
field, or use the abbreviated mnemonic, for
example, in = C_IN.
-k keydir:keyname
Sign the query with the TSIG key named keyname
that is in the directory keydir.
-envsav
Specifies that after all of the arguments are
parsed, the dig environment should be saved to a
file to become the default environment. This is
useful to bypass the standard set of defaults
and use a custom set 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. 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.
LOCALDEF is specific to the dig resolver, and
will not affect operation of the standard
resolver() library.
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. The DiG.env file contains binary data
and should not be modified directly.
-envset
Specifies that after the arguments are parsed,
the dig environment becomes the default environ-
ment for the duration of the batch file, or
until the next line that specifies -envset. This
flag is set by including it in a line in a dig
batch file. It only affects batch query runs.
- [no] stick
Specifies that the dig environment, either as
read initially or set by the -envset option, 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, that
is, they are not restored to the "sticky"
default. This option only affects batch query
runs.
+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(1M). If an option requires a parameter, the
form is as follows:
+ keyword [=value]
Most keywords can be abbreviated. The parsing of the
``+'' options is very simplistic. A value must not
be separated from its keyword by white space. The fol-
lowing keywords are currently available:
Keyword Abbreviation Meaning [default]
[no] debug [deb] Turn on or off debugging mode[deb]
[no] d2 Turn on or off extra debugging mode
[nod2]
[no] recurse [rec] Use or do not 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 or do not use virtual circuit
[novc]
[no] defname [def] Use or do not use default domain
name
[def]
[no] search [sea] Use or do not use domain search
list
[sea]
domain=NAME [do] Set default domain name to NAME
[no] ignore [i] Ignore or do not ignore truncated
errors
[noi]
[no] primary [pr] Use or do not use primary server
[nopr]
[no] aaonly [aa] Authoritative query only flag
[noaa]
[no] cmd Echo parsed arguments [cmd]
[no] stats [st] Print query statistics [st]
[no] Header [H] Print basic header [H]
[no] header [he] Print header flags [he]
[no] ttlid [tt] Print TTLs [tt]
[no] trunc [tr] Truncate origin from names [tr]
[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]
[no] dnssec [dn] Set the DNSSEC OK bit in the OPT
pseudo record [nodn]
pfdef Set to default print flags
pfmin Set to minimal default print flags
pfset=# Set print flags to #. The value of
# can be
hex, octal, or decimal.
pfand=# Bitwise and print flags with #
pfor=# Bitwise or print flags with #
The retry and time options affect the retransmission
strategy used by the 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
dig always uses a value of 1 for num_servers.
ENVIRONMENT VARIABLES
LOCALRES
File to use in place of /etc/resolv.conf
LOCALDEF
default environment file
FILES
/etc/resolv.conf
Initial domain name and name server addresses
./DiG.env
Default save file for default options
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWcsu |
|_____________________________|_____________________________|
| Interface Stability | External |
|_____________________________|_____________________________|
SEE ALSO
in.named(1M), nslookup(1M), resolver(3RESOLV), attributes(5)
Mockapetris, Paul. RFC 1035, Domain Names - Implementation
and Specification. Network Working Group. November 1987.
BUGS
dig does not consistently exit with appropriate status mes-
sages when a problem occurs somewhere in the resolver(),
although most of the common exit cases are handled. This can
be problematic when running in batch mode. If dig 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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