Step 9: Enable sending of non-local messages to other mail servers

Non-local mail is mail that must go through a Mail Transfer Agent (MTA) to get to another host. SMTP supports the following configuration statements to assist in forwarding non-local mail:

IPMAILERNAME, for non-local mail destined for SMTP servers in the IP network using a hostname
IPMAILERADDRESS, for non-local mail destined for SMTP servers in the IP network using a static IP address
MAILER, for non-local mail destined for SMTP servers in the NJE network using the JES spool

Restriction: You cannot use the IPMAILERNAME statement, the IPMAILERADDRESS statement, or the MAILER statement with the UNKNOWN option simultaneously.

For more information regarding these configuration statements, see z/OS Communications Server: IP Configuration Reference.

The SMTP server can be configured to send all your non-local TCP/IP SMTP mail to a specified mail server, or mail relay. You might need to do this if you have installed a firewall. One way to accomplish this is by using IPMAILERADDRESS, making both of the following changes to your hlq.SMTP.CONFIG data set:

Inhibit SMTP from attempting to resolve non-local hostnames by specifying the following statement in your SMTP.CONFIG data set:
```
RESOLVERUSAGE NO
```
Update the SMTP.CONFIG file to redirect mail to a specific server using the IPMAILERADDRESS statement:
```
IPMAILERADDRESS ip_address
```
where ip_address is address of the mail server that can perform the hostname resolution.