nmap --script resolveall --script-args newtargets -p25 rr-test.jacobdevans.com

Starting Nmap 7.01 ( https://nmap.org ) at 2017-04-12 14:29 EDT
Nmap scan report for rr-test.jacobdevans.com (104.244.74.27)
Host is up (0.090s latency).
Other addresses for rr-test.jacobdevans.com (not scanned): 2605:6400:10:434::10 2605:6400:20:931::10 2605:6400:30:fb26::10 199.195.250.251 209.141.51.12
rDNS record for 104.244.74.27: lux.jacobdevans.com
PORT   STATE    SERVICE
25/tcp filtered smtp

Nmap done: 1 IP address (1 host up) scanned in 1.39 seconds