Nmap scan report for dns-external-master.amazon.com (204.74.108.1)
Host is up (0.00041s latency).
rDNS record for 204.74.108.1: pdns1.ultradns.net
Not shown: 999 filtered tcp ports (no-response)
PORT STATE SERVICE
53/tcp open domain
Nmap done: 1 IP address (1 host up) scanned in 5.04 seconds