Blocking spam with Realtime Black Lists and Symantec Mail Security 5.0.x for Microsoft Exchange

Products

• Mail Security for Microsoft Exchange

Issue/Introduction

You need to know how to configure Symantec Mail Security 5.0 for Microsoft Exchange to use a Realtime Black List (RBL) to block spam.

Resolution

An RBL is a DNS-based list that identifies known sources of spam email. You can configure Symantec Mail Security 5.0 for Microsoft Exchange to use a DNS-based RBL to help stop spam email. When the IP address of a sending mail server matches an RBL entry, the email stops.

You can also configure sender whitelists and recipient whitelists to bypass the RBL check.

To configure RBL domains for Symantec Mail Security 5.0 for Microsoft Exchange

1. In the Symantec Mail Security console, on the primary navigation bar, click Policies.
2. On the sidebar, under Antispam, click Blacklist and Whitelist.
3. In the Real-time blacklist domains box, type the name of your realtime blacklist provider's domain. For example, "rbl.blacklistprovider.org".
   You can add more than one domain by pressing Enter after each domain that you type.
4. Click Deploy changes/Deploy all.

Email that originates from any IP address that matches an RBL entry is stopped as spam.

To configure a sender white list for Symantec Mail Security 5.0 for Microsoft Exchange

1. In the Symantec Mail Security console, on the primary navigation bar, click Policies.
2. On the sidebar, under Antispam, click Blacklist and Whitelist.
3. In the content area, under Allowed Senders, check Bypass real-time blacklist and spam detection for messages sent from the following.
4. In the Email and domain addresses box, type the domains and email addresses to bypass for spam processing.
   If you add a domain to the whitelist, subdomains of that domain are also included. For example, the domain "@symantecexample.com" also includes "@mail.symantecexample.com."
5. Click Deploy changes/Deploy all.

Email that originates with addresses or domains in the whitelist is not checked for spam.

To configure an unfiltered recipient list

1. In the Symantec Mail Security console, on the primary navigation bar, click Policies.
2. On the sidebar, under Antispam, click Blacklist and Whitelist.
3. In the content area, under Unfiltered Recipients List, check Bypass real-time blacklist and spam detection for messages sent to the following.
4. In the Email and domain addresses box, type the full email addresses (one address per line) of the recipients for which spam processing is bypassed.
   You can add up to 50 addresses.
5. Click Deploy changes/Deploy all.

Email that is addressed to these recipients is not checked for spam.


Technical Information
Other information.

• Symantec does not provide an RBL database. If you plan to use the RBL feature, you must find an RBL provider. Some RBL services are free, and some require a subscription. To use an RBL with Symantec Mail Security 5.x for Microsoft Exchange, the RBL service provider that you choose must support IP-based (ip4r) lookups.
• Symantec Mail Security version 5.0.x drops messages after receipt of the SMTP message "RCPT TO:"