Using the SMTP Proxy

The SMTP proxy provides a relay for email. It can restrict access based on source address, as well as the domain name of the originating address, and the source and destination mailbox addresses presented within the SMTP protocol (envelope). The source (the sender's address) is compared to the list of spam domains; if the address matches any specific spam domain, the packet gets dropped. The destination (the recipients's address) is compared with the local domain to see if relaying is being attempted. If relaying is allowed, the email message gets passed through, if not, the email message gets dropped.

Be sure you have defined any necessary spam and relay restrictors (see "To Add Spam Domains" and "To Delete Spam Domains").

To Use the SMTP Proxy

1. Point the MX record for the domain to the proxy for mail to be processed properly.

   SMTP connection is then made to the proxy rather than to the actual SMTP server.

2. Point the destination in the rule to the actual SMTP server.