SpamStick overview

Overview -- In A Nutshell

SpamStick is an option add-on spam filtering service that we offer to customers who are running their own mail server and either don't want to maintain their own spam filtering software, or are looking for a solution that offers more effective spam filtering.  Here is how the service works:

1.  Incoming mail for your domain comes to our geographically-redundant spam filtering servers

2.  Our servers filter the good mail from the bad

3.  The good mail is relayed to your mail server, while the bad mail is rejected or put into a quarantine.

Details of How It Works

Domain Aliases

Domain aliases can be added at no additional cost that will behave exactly as the main domain.  Read more here.

Configuration of Email Addresses

Our system uses SMTP callouts to the destination mail server to determine which addresses are valid and invalid.

The filtering servers do a 'null sender' callout. This means that the filtering server will connect to your destination server, using a sender of "<>" (just as a bounce message does), and the real recipient. After checking the recipient, the connection will be properly closed (i.e. no message is actually sent). You need to ensure that your destination servers will correctly verify addresses in this fashion. 

Our systems then cache the result (either a valid or invalid email address) for up to 2 hours.  This way, our systems will not accept mail for email addresses that are not valid on your server.


SpamStick is priced at $10/month per domain, with up to 25 users per domain.  A 30 day free trial is available.  Please contact us by opening a support ticket if you'd like to have this added to your account, or for pricing on larger installations.


Instantly deploy a BSD cloud VPS with RootBSD

deploy instantly

  • Fast SSD hosting
  • Full root access
  • IPv6 and IPv4 enabled hosting
  • Over 25 data center locations worldwide
  • Friendly and knowledgeable support
  • Build with current FreeBSD, OpenBSD, NetBSD, Linux releases