Starting Nmap 7.01 at 2016-09-26 18:54 CEST Nmap scan report for mypage.com (IP-ADRESS)
I'm a Ubuntu beginner. I've set up a dyndns service to redirect the connection for my domain. I've turned off the firewall.
When I type
sudo nmap IP-ADRESS
it shows:
Host is up (0.93s latency).
rDNS record for IP-ADRESS: IP-ADRESS.cable.dynamic.surfer.at
Not shown: 994 filtered ports
PORT STATE SERVICE
20/tcp closed ftp-data
21/tcp closed ftp
23/tcp open telnet
80/tcp closed http
443/tcp closed https
8089/tcp closed unknown
Why is only the 23 port open? What is closing the other ports?
I use a router (for the dyndns service) and set the 23,80,443 ports free.