How to configure DNS Blackhole Lists (DNSBL) in Plesk?

Question

• How to configure DNS Blackhole Lists (DNSBL) in Plesk?
• It it possible to use DNS blacklists for incoming mail in Plesk?

Answer

You may configure and use free and paid subscription blackhole lists with your Plesk server.

Note: A DNSBL is a Domain Name System Block List, which is essentially a list of IP address ranges or other information compiled and presented as a DNS zone that can be used for incoming spam blocking for mailboxes located on your Plesk server.

Warning: If you use the Qmail mail server and switch on DNSBL, senders with IP addresses from the blackhole list will not be able to send email even if they pass SMTP authentication. To avoid this problem, switch on the message submission as described in Configuring Server-Wide Mail Settings.

To switch on spam protection based on DNSBLs in Plesk, you should follow these steps:

1. Go to Tools & Settings > Mail Server Settings (in the Mail group).

2. Activate Switch on spam protection based on DNS blackhole lists checkbox.

3. In the DNS zones for DNSBL service input box, specify the host name that your mail server should query, for example:

   CONFIG_TEXT: bl.0spam.org

4. Click OK

Other free DNSBL examples:

• b.barracudacentral.org
• bl.mxrbl.com
• all.spamrats.com
• dnsbl.justspam.org

Even more examples are available here.

Additional Information

Plesk Obsidian documentation | DNS Blackhole Lists