In DNS terms, if the ip address is a.b.c.d, you want to lookup the "PTR" (not "A"!) tag for d.c.b.a.in-addr.arpa. That's what gethostbyaddr does: 

use Socket qw( AF_INET inet_aton );

my $name = gethostbyaddr(inet_aton('69.147.76.15'), AF_INET);
print "$name\n";

[download]
f1.www.vip.re1.yahoo.com

[download]

In reply to Re: Reverse nslookup by ikegami
in thread Reverse nslookup by Anonymous Monk

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