Email Routing

You can route email destined for particular email domains either to a specific mail server, or by using DNS MX records. This mechanism allows you to specify where to direct:

You can use a wildcard * when specifying a domain name, for example to specify a mail server for external delivery if you are not using DNS. See these Closedexample uses of wildcards.

Use of wildcards when specifying domains

You can specify a wildcard * in a domain name in the routing table, as a prefix only, for example *.yourcompany.com.

If you enter just * as the domain, the Clearswift Gateway uses that route for any domains that do not have entries higher in the table.

The order of entries in the routing table does not have an impact on which entry is used, except where two entries use the same domain name. In this case, the first entry is used.

For example, consider the following routing table:

Domain Route

inside.yourcompany.com

To server at <hostname:port>

inside2.yourcompany.com

To server at <hostname:port>

*

To server at <external server hostname:port>

somegateway.com

Use DNS MX record

In the above example, mail for all domains except inside.yourcompany.com and inside2.yourcompany.com is routed to the external mail server specified by the * entry.

To add a route for a domain

  1. From the System Center Home page, click SMTP Settings. The SMTP Settings page appears.
  2. Click Mail Domains and Routing to display the Mail Domains and Routing page. Select the Email Routing tab.

  3. Click New to create a new route. The Add Email Route dialog is displayed.

  4. In the Add Email Route dialog, enter the following information:

    • In Domain, specify the domain for which you want to provide routing information.

    • In Route, select how you want the routing to be applied:

      • Uses DNS Mail Exchange records to route traffic to the specified domain.

      • You can use Server and Port to specify a server's fully qualified host name or IP address.

      • Select a pre-configured MTA Group from the list of available options. MTA Groups can be used to load-balance a group of servers, or to manage what happens if one of them fails. See MTA Groups for more information.

          Predictive search is enabled on the MTA Groups drop-down. You can type an entry to autocomplete the search as you type.
    • Select a Connection Profile, which defines your TLS settings. The information box at the top of the dialog displays the status of your authentication and TLS settings.
    • You can also include any authentication settings that might be required to complete the SMTP connection.
      1. Select the Authentication type required by the server (AUTH PLAIN/LOGIN or NONE).
      2. Enter the mail server's Username and Password and then Confirm Password.
        If you have multiple routes to the same server, you must ensure that the same connection profile is selected in order for TLS to be applied. You must also ensure that the AUTH configuration is the same for all routes to the same server when using an IP address for routing.

      It is highly recommended that you enable TLS on authenticated SMTP connections.
  5. Click Add to add the entry to the routing table.

  6. To change the priority of an entry in the routing table, select the entry and click or as required.

  7. To edit the route, select an entry from the table and click Edit.

To remove a route for a domain

  1. Move the mouse pointer over the Email Routing area, select the item in the list and click Delete. A Confirm Delete dialog box is displayed stating 'Are you sure you want to delete the route?'.

  2. Click Yes to remove the entry from the Email Routing table.

See also...