Specifying Routing of Email

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 Clearswift Gateway is to direct:

Messages for your domains (incoming mail), received from the Internet.

Messages for domains other than your own (outgoing mail), forwarded from an internal SMTP Gateway.

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. If you include wildcards, the order of the entries in Clearswift Gateway's routing table determines their relative priority. See these

example 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, Clearswift Gateway uses that route for any domains that do not have entries higher in the table.

Any entries below a * entry in the table are ignored. You can use this feature to disable an entry in the table temporarily, if required: simply move it below the * entry.

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. The routing entry for somegateway.com is ignored.

To add a route for a domain:

From the System Center Home page, click SMTP Settings. The SMTP Settings page appears.

Select Mail Domains and Routing to display the Mail Domains and Routing page.

Click the Email Routing tab. The Email Routing area contains a table listing current routing information.

Click

New. The Add Email Route dialog appears.

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 either 'Using DNS' or 'To a server'.

If you specified 'To a server' above, specify the server's fully qualified host name or IP address, and the port number to use.

Click Add to add the entry to the routing table.

To change the priority of an entry in the routing table, select the entry and click

as required.

To edit a route for a domain:

From the System Center Home page, click SMTP Settings. The SMTP Settings page appears.

Select Mail Domains and Routing to display the Mail Domains and Routing page.

Click the Email Routing tab. The Email Routing area contains a table listing current routing information.

Select the entry you wish to edit in the Email Routing area and click

Edit. The Edit Email Route dialog appears.

In the Edit Email Route dialog, modify the following information as required:

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

In Route, select either 'Using DNS' or 'To a server'.

If you specified 'To a server' above, specify the server's fully qualified host name or IP address, and the port number to use.

Click Update to modify the entry in the routing table.

To change the priority of an entry in the table, select the entry and click

as required.

If the Gateways are configured as a group, any group changes should be applied to each Gateway. If you change any configuration settings you must apply the new configuration for the new settings to take effect.