Apple Mac OS X Server (Administrator’s Guide) - Manual (Page 390)

390 Chapter 9
m You may need to use this setting to deliver outgoing mail through a firewall set up by your
organization. In this case, your organization will designate a particular server for relaying
mail through the firewall.
m You may find this setting useful if your server has slow or intermittent connections to the
Internet, or if you are billed by the number of connections you initiate.
To relay SMTP mail through another server:
1 In Server Settings, click the Internet tab.
2 Click Mail Service and choose Configure Host Settings.
3 Click the Outgoing Mail tab.
4 Click “Relay all SMTP mail via” and enter the DNS name or IP address of the server that
provides SMTP relay.
5 Click Save.
Note: This option is disabled if the pop-up menu is set to “Limit to local users.”
Changing the SMTP Response Names
When your server connects with another server to send outgoing mail, your SMTP mail
service identifies itself by sending a name. Your SMTP service also sends its name when
another server contacts your server to deliver incoming mail. You can specify the name that
your SMTP service sends for incoming connections and the name it sends for outgoing
connections.
m The incoming and outgoing SMTP response names are typically the same.
m The incoming and outgoing response names should match the DNS name that another
server would get by doing a reverse DNS lookup of your server’s IP address.
m If your server connects to the Internet via an Internet gateway or router that uses
Network Address Translation (NAT), your server effectively has the IP address of the
Internet gateway or router. In this case, the incoming and outgoing response names
should match the DNS name that another server would get by doing a reverse DNS
lookup of the Internet gateway’s IP address. An AirPort Base Station is an example of an
Internet gateway that can be configured to use NAT.
To specify the SMTP response names:
1 In Server Settings, click the Internet tab.
2 Click Mail Service and choose Configure Mail Service.
3 Click the Protocols tab and choose Apple Mail Service SMTP from the pop-up menu.
4 Click SMTP Options.
5 Enter the incoming response name and the outgoing response name, then click Save.