UnicornCloud · Email Hosting


We use some blacklists cause they really help us in not getting spam. We use the following DNS lists:

  • zen.spamhaus.org
  • b.barracudacentral.org

Other things blocked on the SMTP port (25)

  • People who use localhost in EHLO command
  • People who use IP addresses in EHLO command
  • People who impersonate Google, Yahoo or Sohu in EHLO command
  • Known ADSL hostnames


We use fail2ban to monitor SSH, Dovecot and Postfix logins. If you try to authenticate with a wrong password more than 3 times in a row in 5min, you will get banned for 4h.

If you get a message you are blocked because one of the blacklists or the other shit, stop using port 25?!

Currently banned

Country IP Netname Description
No one!