CONFIGURING


Restricting who can send Internet mail to your users

Unsolicited commercial e-mail (UCE) can flood your server with numerous copies of the same message. Accepting UCE reduces performance and consumes system resources. You can specify restrictions to prevent UCE from being routed to or relayed through your server. Specifying restrictions prevents malicious users from using your system to spoof addresses or send UCE.

About this task

To save system resources, before it accepts a message, the Domino® SMTP listener checks the Mail From address specified in the message envelope during the SMTP transaction. If you set the Domino server to deny mail from a particular source, Domino denies it whenever that source is encountered -- for example, if users from a denied domain send mail through a relay, Domino denies it based on its origin from that domain. Domino creates an entry in the log file (LOG.NSF) whenever a message is rejected.

Note: SMTP can resolve names for group types of Mail-only or Multi-purpose. When you create or modify the SMTP and Router settings in the Configuration Settings document, be sure to enter group names that have a group type of Mail-only or Multi-purpose. These groups must be in the primary directory. This applies to settings on the Restrictions tab, the SMTP Inbound Controls tab, and the SMTP Outbound Controls tab.

Procedure

1. Make sure you already have a Configuration Settings document for the server(s) to be configured.

2. From the Domino Administrator, click the Configuration tab and expand the Messaging section.

3. Click Configurations.

4. Select the Configuration Settings document for the mail server or servers you want to restrict mail on, and click Edit Configuration.

5. Click the Router/SMTP -> Restrictions and Controls -> SMTP Inbound Controls tab.

6. Complete these fields and then click Save & Close:


7. Reload the SMTP task, or update the SMTP configuration to put changes into effect.

Related concepts
Restricting SMTP inbound routing
The Domino server log file (LOG.NSF)

Related tasks
Creating a Configuration Settings document
Stopping and starting the Domino SMTP service
Updating the SMTP configuration
Preventing unauthorized SMTP hosts from using Domino as a relay
Restricting inbound SMTP connections
Restricting mail routing based on domain, organization, and organizational unit
Restricting users from receiving Internet mail
Restricting users from sending mail to groups in the Domino Directory