[root@scw-naughty-maxwell ~]# nmap -p 3306 5.2.81.161

Starting Nmap 6.40 ( http://nmap.org ) at 2020-02-21 14:33 UTC
Nmap scan report for sentinus.alastyr.com (5.2.81.161)
Host is up (0.060s latency).
PORT     STATE SERVICE
3306/tcp open  mysql

Nmap done: 1 IP address (1 host up) scanned in 0.22 seconds