Hello all, I'm trying to calculate and print out all subnets of prefix length x from a subnet with a prefix length y \. For example: I want to split a /40, say 2001:0DB8::/40 into /56 subnets. I thought about using NetAddr::IP , for example:

use NetAddr::IP;
my $sub6 = new NetAddr::IP '2001:db8::/40';

my $i=1;
while ($sub6 < $sub6->broadcast) {  # should've been <= but it does no
+t seem to work
        if ($i==4722366482869645213696) { # that many addresses in a /
+56
                print "ip = $sub6\n";
                $i=1;
        }
        $sub6 ++;
        $i++;
}
print "ip = $sub6\n";  # need to print last address

[download]

the above probably works but seems so inefficient and terribly slow. Any ideas would be greatly welcomed!

In reply to efficient IPv6 subnetting by Anonymous Monk

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