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Keyword Abbreviation Meaning (Default)
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]
[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]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: 


August 30, 1990

for i = 0 to retry _ 1

for j = 1 to num_servers

send_query

wait((time * (2**i)) / num_servers)

end

end

Note that dig always uses a value of 1 for num_servers.

DETAILS

dig once required a slightly modified version of the BIND resolver (3) library. BIND's resolver has (as of BIND 4.9) been augmented to work properly with dig. Essentially, dig is a straightforward (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.

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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(8) authored by Andrew Cherenson.

BUGS

dig has a serious case of "creeping featurism," the result of considering several potential uses during its 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 (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.

SEE ALSO

named(8), resolver(3), resolver(5), nslookup(8)

30 August 1990

dnsquery

dnsquery—Query domain name servers using resolver

SYNOPSIS 


dnsquery [-n nameserver] [-t type] [-c class] [-r retry] [-p retry period]

[-d] [-s] [-v] host

DESCRIPTION

The dnsquery program is a general interface to nameservers via BIND resolver library calls. The program supports queries to the nameserver with an opcode of QUERY. This program is intended to be a replacement or supplement to programs like nstest, nsquery, and nslookup. All arguments except for host and ns are treated without case-sensitivity.

OPTIONS
_n The nameserver to be used in the query. Nameservers can appear as either Internet addresses of the form w.x.y.z or can appear as domain names. (default: as specified in /etc/resolv.conf)
_t The type of resource record of interest. Types include:
A Address
NS Nameserver
CNAME Canonical name
PTR Domain name pointer
SOA Start of authority

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WKS Well-known service
HINFO Host information
MINFO Mailbox information
MX Mail exchange
RP Responsible person
MG Mail group member
AFSDB DCE or AFS server
ANY Wildcard

NOTE
Any case may be used (the default is ANY)

_c The class of resource records of interest. Classes include the following:
IN Internet
HS Hesiod
CHAOS Chaos
ANY Wildcard

NOTE
Any case may be used (the default is IN).

-r The number of times to retry if the nameserver is not responding. (default: 4) _p Period to wait before timing out. (default: RES_TIMEOUT) options field. (default: any answer) _d Turn on debugging. This sets the RES_DEBUG bit of the resolver's options field. (default: no debugging) _s Use a stream rather than a packet. This uses a TCP stream connection with the nameserver rather than a UDP datagram. This sets the RES_USEVC bit of the resolver's options field. (default: UDP) _v Synonym for the s flag. host The name of the host (or domain) of interest.

FILES

/etc/resolv.conf To get the default ns and search lists.
<arpa/nameser.h> List of usable RR types and classes
<resolv.h> List of resolver flags

SEE ALSO

nslookup(8), nstest(1), nsquery(1), named(8), resolver(5)

DIAGNOSTICS

If the resolver fails to answer the query and debugging has not been turned on, dnsquery will simply print a message like this: 


Query failed (rc = 1) : Unknown host

The value of the return code is supplied by h_errno.

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