Technical data

Configuring and Managing SMTP
17.1 Key Concepts
In this example, when SMTP receives a mail message destined for a domain
outside of the abc.com domain, it uses the list of MX records to send the mail to
the entity called relay.abc.com . Even when mail is routed through the alternate
gateway, the MX lookup list is used.
This type of configuration provides redundancy. Even if one or more of the
systems pointed to by the MX records is down, mail can be routed through one of
the systems that is running.
If the alternate gateway was reached through a simple A record (hostname)
lookup and the host was down or could not be reached, all outbound mail outside
the zone would have to wait until the host came back on line.
You can define the alternate gateway using an IP address; this bypasses the MX
lookup logic. For example:
CPIP> SET CONFIGURATION SMTP/ALTERNATE=GATEWAY=1.2.3.4
In this case, all mail destined for the alternate gateway will go to the specified IP
address (1.2.3.4) with no MX lookup.
17.2 Configuring SMTP
Use the configuration procedure TCPIP$CONFIG to set up SMTP on your host.
If you need to reconfigure or further refine your SMTP environment, use the SET
CONFIGURATION SMTP command. With this command, you can change the
way SMTP:
• Relays messages
• Determines the route
• Determines how many times it retries a relay and the length of time between
delivery attempts
• Sends and receives timeouts
For a complete description of this command, its qualifiers, and options, see
Compaq TCP/IP Services for OpenVMS Management Command Reference.
17.2.1 Mail Utility Files
Table 17–2 lists the utility files created during the SMTP configuration.
Table 17–2 Default SMTP Utility Files
File Name Description
LOGIN.COM Used by the auxiliary server.
TCPIP$SMTP_RECV_RUN.COM Used by the auxiliary server, and stored in the
TCPIP$SYSTEM directory.
TCPIP$SMTP_LOGFILE.LOG Log of mail queue and symbiont activities.
TCPIP$SMTP_RECV_RUN.LOG Log of incoming mail.
To analyze the consistency of the SMTP queues against the directories containing
the SMTP utility files, enter the ANALYZE MAIL command.
17–6 Configuring and Managing SMTP