#!/usr/bin/perl -w
use strict;
use warnings;

my %IPs;
while(<DATA>) {
   if (m#^(\d+)([\s\d/]+)IP\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)#) {
       push @{$IPs{$1}}, sprintf("%-10s %-24s %s", $1 . $2, $3, $4);
   }
}

print "KEY   \tIP         NAME                     STATUS\n"
.     "------\t---------- ------------------------ --------------\n";
for my $IP (sort keys %IPs) {
   print sprintf("%-6s\t",$IP), join("\n\t", sort @{$IPs{$IP}}), "\n";
}

__DATA__
2345      IP   NAME.com         online IPADDRESS1
2345/1243 IP Name-interface.com inactive IPADDRESS2
2345/3213 IP NAME-interfce2.com online IPADDRESS1
2345/1212 IP Name-interface3.com online IPADDRESS3
4321      IP   CNAME.com         dead IPADDRESS_1
4321/1643 IP CName-interface.com online IPADDRESS_1
4321/3673 IP CNAME-interfce2.com online IPADDRESS_2