yPass.net

How to perform an Inverse Query (PTR query):

require_once("Net/DNS.php");
$res = new Net_DNS_Resolver();
$res->debug = 1;
$answer = $res->search("208.77.188.166");
echo "<BR><HR><BR>";
print_r($answer);

This example will query the name server and output the following:

;; search(166.188.77.208.in-addr.arpa., PTR, IN)
;; query(166.188.77.208.in-addr.arpa., PTR, IN)

;; using extended PHP sockets

;; send_udp(208.79.80.18:53): sending 45 bytes
;; timeout set to 5 seconds
;; answer from 208.79.80.18:53: 74 bytes
;; HEADER SECTION
;; id = 2208
;; qr = 1    opcode = QUERY    aa = 0    tc = 0    rd = 1
;; ra = 1    rcode  = NOERROR
;; qdcount = 1  ancount = 1  nscount = 0  arcount = 0

;; QUESTION SECTION (1 record)
;;
;166.188.77.208.in-addr.arpa.	IN	PTR

;; ANSWER SECTION (1 record)
166.188.77.208.in-addr.arpa.	21600	IN	PTR	www.example.com.

;; AUTHORITY SECTION (0 records)

;; ADDITIONAL SECTION (0 records)


Net_DNS_Packet Object
(
    [debug] => 1
    [header] => Net_DNS_Header Object
        (
            [id] => 2208
            [qr] => 1
            [opcode] => QUERY
            [aa] => 0
            [tc] => 0
            [rd] => 1
            [ra] => 1
            [rcode] => NOERROR
            [qdcount] => 1
            [ancount] => 1
            [nscount] => 0
            [arcount] => 0
        )

    [compnames] => Array
        (
        )

    [answerfrom] => 208.79.80.18
    [answersize] => 74
    [question] => Array
        (
            [0] => Net_DNS_Question Object
                (
                    [qname] => 166.188.77.208.in-addr.arpa
                    [qtype] => PTR
                    [qclass] => IN
                )

        )

    [answer] => Array
        (
            [0] => Net_DNS_RR_PTR Object
                (
                    [name] => 166.188.77.208.in-addr.arpa
                    [type] => PTR
                    [class] => IN
                    [ttl] => 21600
                    [rdlength] => 17
                    [rdata] => wwwexamplecom
                    [ptrdname] => www.example.com
                )

        )

    [authority] => Array
        (
        )

    [additional] => Array
        (
        )

)