Black List of Latvian Spammers

1. Using the Blacklist

E-mail server software receives and sends e-mail messages, but it should be able to ascertain whether or not an incoming message should be rejected due to not being in compliance with service guidelines, normative acts, or other criteria. The goal of a blacklist is to reduce the number of received e-mails from servers that do not comply with standards or normative act requirements, as well as to ensure normal server operation and minimise the chance of being blacklisted by foreign or other service providers.

If this description does not include your e-mail software, please use your e-mail server documentation to establish how to correctly implement blacklisting.

2. Blacklisting in several popular e-mail server software

A blacklist consists of IP addresses that have sent unwanted messages, or spam. When using a blacklist, it’s possible to configure the receiving e-mail server to stop the spam in the very beginning stages of communication: if the sender’s IP address is included in the blacklist, the message is not processed further.

Using the Blacklist in various e-mail server software:


Editing the /etc/postfix/ or main.cof file:
smtpd_recipient_restrictions =


1. Add this line to your server config.m4
FEATURE(`dnsbl', `', `"Mail blocked based on BLW.CERT.LV:"$&{client_addr}')dnl

2. For newer versions:
FEATURE(`enhdnsbl', `', `""$&{client_addr}', `t')dnl

3. Recompile using config.m4

4. Restart Sendmail

Microsoft Exchange

Microsoft Exchange 2003 SP2 and newer versions support blacklist use if you are using the Microsoft Exchange Server Intelligent Messaging component. To read more about its use, see
In the Connection filter parameter, enter as the “DNS Suffix of Provider”

3. An example of integrated use of the blacklist and other tools

Black List of Latvian Spammers (MMS) can be used with SpamAssasin software to ensure additional functionality.

If a message is sent from an IP address on the blacklist, it has 3 points added to the score, which influences its fate in further spam filtration.

In this case, the processing of a message is not always cancelled even if the sender’s IP address is in the blacklist.

SpamAssasin configuration:

header RCVD_IN_CERTLVBL eval:check_rbl('certlv', '')
describe RCVD_IN_CERTLVBL Received via a relay listed by BL

4. Tips

aps_rbl_domains =,,

smtpd_recipient_restrictions =

5. MMS usage possibilities

6. Necessary resources and possible problems when using the Blacklist

So that end users (e-mail accounts) have a chance to choose whether or not to use filtration in their inbox, it’s recommended to use the MMS as one of the parameters in the SpamAssasin software.