Inbound Gateways

The purpose of an inbound gateway is to reduce server load by pre-processing incoming messages prior to the messages being handed off for delivery to the primary SmarterMail server. For example, spam checks and antivirus scans should be performed by inbound gateways, especially in larger environments. This frees up the primary server so all it has to do is deliver messages to individual users. An Inbound Gateway is generally a standalone server, processing messages for other mail servers, and most often doesn't act as both an Inbound Gateway AND primary mail server.

To set up a SmarterMail installation as an Inbound Gateway, log into the SmarterMail server as a System Administrator. In the Settings area, click on Gateways / Failover in the navigation pane and select the Inbound tab.

NOTE: This tab should only be used to designate the server you're logged into as an Inbound Gateway. Any existing Inbound Gateways SHOULD NOT be added to this tab.

To set the server as a new inbound gateway, click the New button. When adding or editing an entry, the following settings will be available:

Options

Gateway Mode - The function that the inbound gateway will perform. If the inbound gateway is set to Backup MX, it will only receive messages when your primary server is down. If the inbound gateway server is set to Domain Forward, it will receive all messages and forward them to your primary server.
IP Addresses (single or range) - The IP address, or range of IP addresses, of the primary mail server.
Status - New gateways default to a status of Enabled. To temporarily stop an inbound gateway, you can change the status to Disabled.
SMTP User Verification - This setting makes SmarterMail verify that a recipient exists when accepting mail from the gateway.

Domains

This card is only available if the gateway mode is set to Domain Forward. Domain forwarding allows you to easily send mail through one server to another. This will allow your server to act as an inbound gateway to your network, and permit you to have a single point of entry for inbound SMTP traffic.

When messages come in to a forwarded domain, they are run through the command-line .exe referenced in the Protocols settings. If a delivery delay has been established for the server, messages are also delayed accordingly. This allows you to establish an inbound server that can run external virus or spam scanners, which can reduce the load on your existing network servers.

Use this card to specify for which domains the inbound gateway will accept mail:

Domain Verification - The method used by the inbound gateway to determine if a domain is valid or not: Specified Domains or All But Specified Domains. List the domain(s) below (one entry per field).

SmarterMail Gateway

Enable SmarterMail Gateway Mode - Select this option to indicate that the inbound gateway server is another SmarterMail server.
SmarterMail URL - The webmail URL for the SmarterMail server being used an an inbound gateway. This will allow the use of web services to verify the users and domains. (NOTE: SmarterMail uses a cache of the domains and users on a server, so if there are any changes (e.g., additions, modifications like enabling/disabling users or domains, or deletions) these changes may not be reflected for up to 10 minutes until the cache is refreshed.)
SmarterMail Username - The identifier used to login to the primary mail server.
SmarterMail Password - The corresponding password used to login to the primary mail server.
User Verification - The method used by the inbound gateway to determine if a user is valid or not. Note: If none is selected, the inbound gateway server will accept all email addresses for the domain. If Web service is selected, the inbound gateway will check with the primary mail server for a list of valid email addresses.

Spam

Use this tab to specify the following spam checks:

Not Spam Action - The action the inbound gateway will perform on messages NOT marked as spam.
Spam Low Action - The action the inbound gateway will perform on messages with a low probability of being spam.
Spam Medium Action - The action the inbound gateway will perform on messages with a medium probability of being spam.
Spam High Action - The action the inbound gateway will perform on messages with a high probability of being spam.