PHP does not resolve .local dns names with gethostbyname - php

Question

I have werid problem with name resolution. I am trying to connect to active directory server. I can successfully get the ldap server address from the SRV recodrs. Then I try to resolve the dns names to IP addresses and it fails:
<?php
echo 'example.com.:' . PHP_EOL;
echo gethostbyname('example.com.');
echo PHP_EOL;
echo 'dc1.veracomp.local.:' . PHP_EOL;
echo gethostbyname('dc1.my-company.local.');
echo PHP_EOL;
echo 'nslookup dc1.my-company.local.:' . PHP_EOL;
echo `nslookup dc1.my-company.local.`;
The example.com is resolved correctly, then the gethostbyname('dc1.my-company.local.') fails after a few seconds returning dc1.my-company.local. instead of the IP address. Still the same PHP script can call nslookup which correctly resolves the domain name...:
example.com.:
93.184.216.119
dc1.my-company.local.:
dc1.my-company.local.
nslookup dc1.my-company.local.:
Server: xxx.xxx.254.117
Address: xxx.xxx.254.117#53
Name: dc1.my-company.local
Address: 192.168.12.21
What is wrong here?
EDIT:
I am asking for name resolution beacuse the real problem i have is that I can connect to ldap://192.168.12.21 or to ldap://dc1.my-company.pl, but I cannot connect to ldap://dc1.my-company.local.
Unfortunatelly the SRV records for _ldap._tcp.my-company.pl returns only local addresses. I do not want to hardcode the .pl address. And I do not understand why I have to manually resolve the local addresses before passing them to Zend_Ldap as a host option.

Answer 1

You should avoid its use in production. DNS Resolution may take from 0.5 to 4 seconds, and during this time your script is NOT being executed.
I use this one; this will be faster and more efficient:
<?php
function getAddrByHost($hosts, $timeout = 3) {
$returnString = '';
foreach ($hosts as $host) {
$query = `nslookup -timeout=$timeout -retry=1 $host`;
if (preg_match('/\nAddress: (.*)\n/', $query, $matches))
$returnString .= trim($matches[1]) . '<br>';
$returnString .= $host . '<br>';
}
return $returnString;
}
$hostArray[] = 'www.example.com';
$hostArray[] = 'dc1.my-company.local';
$returnString = getAddrByHost($hostArray);
echo $returnString;
?>