How to enable internal domain filter in smarter mail

To enable internal domain filtering in SmarterMail, you'll need to follow these steps:

Prerequisites:

  1. You have a SmarterMail server installed and configured.
  2. You have a basic understanding of DNS and email routing.

Step 1: Configure the Internal Domain Filter

  1. Log in to your SmarterMail web interface as an administrator.
  2. Go to Settings > Domain Settings.
  3. Click on the Internal Domain Filter tab.
  4. Enable the Internal Domain Filter by toggling the switch to the "On" position.

Step 2: Configure the Filter Rules

  1. In the Internal Domain Filter tab, click on the Add Rule button.
  2. In the Rule Name field, enter a name for your rule (e.g., "Internal Domain Filter").
  3. In the Condition field, select Domain and choose Is from the dropdown menu.
  4. In the Value field, enter the internal domain name (e.g., @example.local).
  5. In the Action field, select Reject or Redirect depending on your desired action.
  6. Click Save to save the rule.

Step 3: Configure DNS

  1. Update your DNS settings to point the internal domain name to your SmarterMail server's IP address.
  2. Create a DNS record for the internal domain name (e.g., example.local) with a type of MX and point it to your SmarterMail server's IP address.

Step 4: Test the Internal Domain Filter

  1. Send an email from an internal domain email address (e.g., [email protected]) to an external email address.
  2. Verify that the email is rejected or redirected as configured in the internal domain filter rule.

By following these steps, you should now have an internal domain filter enabled in SmarterMail, which will help prevent internal emails from being sent to external domains and reduce the risk of email spoofing attacks.