dns_get_record

karl at influ dot io (2013-04-26 01:38:44)

There's a comment below from 7 years ago regarding BSD and MacOSX, I'd just like to follow up incase some people see that and don't think it'll work on MacOSX.
Software:
System Software Overview:
System Version: OS X 10.8.3 (12D78)
Kernel Version: Darwin 12.3.0
Boot Volume: Macintosh HD
Boot Mode: Normal
Computer Name: Karl’s iMac
User Name: Karl Kloppenborg (karl)
Secure Virtual Memory: Enabled
Time since boot: 10 days 20:24
--------------
# php -a
php > print_r(dns_get_record('google.com', DNS_MX));
Array
(
[0] => Array
(
[host] => google.com
[type] => MX
[pri] => 10
[target] => aspmx.l.google.com
[class] => IN
[ttl] => 749
)
[1] => Array
(
[host] => google.com
[type] => MX
[pri] => 30
[target] => alt2.aspmx.l.google.com
[class] => IN
[ttl] => 749
)
[2] => Array
(
[host] => google.com
[type] => MX
[pri] => 50
[target] => alt4.aspmx.l.google.com
[class] => IN
[ttl] => 749
)
[3] => Array
(
[host] => google.com
[type] => MX
[pri] => 40
[target] => alt3.aspmx.l.google.com
[class] => IN
[ttl] => 749
)
[4] => Array
(
[host] => google.com
[type] => MX
[pri] => 20
[target] => alt1.aspmx.l.google.com
[class] => IN
[ttl] => 749
)
)

rahbari at gmail dot com (2011-12-19 18:45:28)

If only NS records are set (when the domain is not configured on the host), DNS_NS must be used, otherwise an error occurs and it returns nothing!

dylan at pow7 dot com (2009-02-21 11:29:35)

Get more than one type at once like this:
<?php
$dnsr = dns_get_record('php.net', DNS_A + DNS_NS);
print_r($dnsr);
?>

Using DNS_ALL fails on some domains where DNS_ANY works. I noticed the function getting stuck on the DNS_PTR record, which caused it to return FALSE with this error:
PHP Warning:  dns_get_record(): res_nsend() failed in ....

This gets all records except DNS_PTR:
<?php
$dnsr = dns_get_record('php.net', DNS_ALL - DNS_PTR);
print_r($dnsr);
?>

geo at vzemibg dot com (2008-09-30 03:52:56)

Note that if you check a non-existing domain you will get:
Warning: dns_get_record() [function.dns-get-record]: res_nsend() failed in ...
and the function will return an empty srtring (not array). I do not see this described above.

nick at carbidefinger dot net (2008-06-22 08:19:54)

Its worth nothing that this function returns nothing if the server you are running it from is authoritative for the domain you are checking (common on shared hosting platforms) when looking up 'NS' records
In this instance $authns is an array containing no keys or values:
dns_get_record("alocaldomain.com","NS",$authns,$addtl);

marcus at synchromedia dot co dot uk (2006-02-01 16:02:07)

The docs say "nor does it (currently) work on *BSD systems". Unfortunately this includes MacOS X. It's just not there in my build of 5.1.2 running on 10.4.4.

ed at noxserver dot com (2005-03-24 05:44:53)

I recently needed to do some name server and IP discovery on the fly.
Server and domain monitoring system. If you've got a system with dig
the below seems to work fine for discovering name server and a
addresses. Shouldn't be hard for you to modify it for the other records if
needed.
$_REQUEST[url] = "http://www.example.com/";
$url_parts = parse_url($_REQUEST[url]);
$dns = Dig($url_parts[host]);
print_r($dns[name_servers]);
print_r($dns[ips]);
function Dig ($domain) {
$dig = `dig $domain`;
preg_match_all("/in\s+ns\s+(.+?)\s+/is"
,$dig,$name_servers,PREG_PATTERN_ORDER);
preg_match_all("/$domain.\s+[0-9]+\s+in\s+a\s+([0-9.]+)\s+/is"
,$dig,$ips,PREG_PATTERN_ORDER);
$dns[name_servers] = $name_servers[1];
$dns[ips] = $ips[1];
return($dns);
}

axelm-php at nona dot net (2003-05-16 17:06:56)

I've done a backport of the function to PHP4.
It is available as extension at:
http://nona.net/software/dns_get_record/
comments & feedback appreciated.
--
Alexander Mayrhofer
axelm-php@nona.net