SmarterMail 3.x Help
This documentation is for a product that is no longer supported by SmarterTools.

Gateways and Other Server Roles

Please note that SmarterMail was designed to support one server in several of these roles. For instance, one server could act as an Incoming Gateway, an Outgoing Gateway, and a Backup MX.

SmarterMail can also take on one of these roles when placed together with a competing mail server product. For example, using SmarterMail as an outgoing gateway on a server other than your primary mail server may help to resolve problems with stability of other mail server software products.

Primary mail server

  • Use for storing email for defined users.
  • Accessible through POP, SMTP, IMAP, and over the web.
  • To configure:
    1. Follow instructions in online help

Backup MX Server

  • Use as a backup for mail delivery in case of short amounts of downtime or delivery problems on your primary mail server.
  • To configure:
    1. Add a placeholder domain (called "") to open up the port to listen on.
    2. Configure SmartHosting by adding the IP addresses to which delivery should be allowed.
    3. In general settings, change the delivery retry times to 10, 10, 10, and 1440.
    4. In DNS, add secondary MX records pointing to the new server's IP. Set the preference value higher than the main MX record.

Incoming Gateway server

  • Use to host third party anti-virus and/or anti-spam software products in order to reduce load on primary server.
  • Reduces load on primary server by managing all incoming sessions and performing abuse/intrusion detection.
  • To configure:
    1. Enable domain forwarding and add all destination IPs and domain names that will be forwarded.
    2. Add a placeholder domain (called "") to open up the port to listen on.
    3. In DNS, change the MX records of your domains to reference the new gateway server.
    4. Install and configure any third-party anti-virus or anti-spam products, such as Declude JunkMail or Declude Virus.

Outgoing Gateway server

  • Use as a delivery mechanism to reduce load on your primary servers.
  • Also use as a method to combat blacklisting. If the server gets blacklisted, rotate the primary IP on the network card to a different one to send out on the new IP.
  • To configure:
    1. Add a placeholder domain (called "") to open up the port to listen on.
    2. Set relay option in General Settings to "nobody".
    3. Add the primary mail server's IP addresses to the IP Whitelist for SMTP.
    4. In your primary mail server's General Settings page, set the IP address of the gateway server and enable gatewaying.