title: 100% open ports false positive on scanning external Ip's
body: <p>Got a new vps server, which is having a strange problem.
  I tried a number of port scanning utilities (nmap, masscan, zmap, etc), any port I scan on any external Ip is detected as open.
  Tried disabling the  firewall, replacing Ubuntu with Debian, nothing helps. Can't see any possible related errors in journalctl records.
  What could possibly be the issue?</p>