Hi,

Have your code inside the while(1) like below,

my %ipaddress_namei = ();

while(1)
{
        print "Enter IP address of Bond2\n";
        my $bond2 = <STDIN>;
        chomp($bond2);
        if(&validate_ip($bond2))
        {
                $ipaddress_namei{bond2} = {$bond2};
                last;
        }

}

sub validate_ip
{
        #return 0;
        return 1;
}
[download]

It will ask you to enter the IP address, and calls a function to validate the IP address, in function validate_ip do your validation part and return 1 for true, 0 for false, based on that the while will continue to get the input. This code will get the valid IP only once.