SMTP Proxy Rules

After configuring the content filtering, the final step is to create one or more rules that allow SMTP-based email to be served. A typical configuration often allows filtering outside email through the proxy to one or more inside message transfer agents (MTA) such as Solaris mail servers.

The source address for SMTP proxy rules should allow mail from any potential mail-sending address. Restrictions on source addresses in the rule can be useful in blocking abusive mail-originating sites that are stationary with respect to IP addressing.

The destination address for SMTP proxy rules should contain the addresses of one or more MTAs to which the proxy will connect to store and forward the incoming email.