Restricting relays

To prevent people from using your e-mail server for spamming or sending large amounts of bulk e-mail, you can use the relay restriction function to specify as closely as possible who can use your system for relays.

You have six options for allowing relays:

• Allow all relay messages

• Block all relay messages

• Accept relay messages for only recipients in the near domains list

• Accept relay messages from only the address relay list

• Accept relay messages using both the near domains and address relay lists

• Accept relay messages from POP clients for a specified period of time

To specify users that can send e-mail to the Internet, follow these steps:

1. In iSeries™ Navigator, expand your system > Network > Servers > TCP/IP.

2. Right-click SMTP and select Properties.

3. Click the Relay Restrictions tab.

4. Select the appropriate relay restriction from the six options offered here.

   If you choose Accept relay messages for only recipients in the near domains list or Accept relay messages using both the near domains and address relay lists, then you need to click the General tab to list the near domains from which you are accepting relays.

5. Click OK.

6. If the SMTP server is currently running, you need to end and restart the SMTP server for the changes to take effect:

   1. Right-click SMTP and select Stop.

   2. Right-click SMTP and select Start.

• Accepting relay messages from Post Office Protocol clients
  One of the options for relay restriction enables Post Office Protocol (POP) clients to relay messages through Simple Mail Transfer Protocol (SMTP) for a specified period of time after they log on to the POP server.

• Using relay restriction and connection restriction functions together
  The i5/OS^® operating system enables you to use the relay restriction function along with the connection restriction function to carefully control who can access your e-mail server.

Parent topic:

Related concepts
Controlling e-mail access