maRBL is a Postfix policy daemon that enables users to initiate any Postfix action upon the resolution of an RBL match.
The maRBL project is a Postfix policy daemon that allows users to trigger a Postfix action in response to an RBL match. When it comes to spam filtering, there are only a few practical options available, and none of them can guarantee 100% effectiveness. Statistical filters come close to perfection but require significant CPU time and have limited options for blocking hosts outright.
However, RBLs can provide a simple and efficient solution to the problem. They are fast and reliable, but their effectiveness can be hindered by false positives. This is because RBL administrators need to be trusted to add and remove hosts accurately and in a timely manner. Unfortunately, many lists rely on humans to manage them, which can lead to errors and oversights. In some cases, lists may block entire IP ranges to put pressure on ISPs to address their spam problem.
Greylisting is another option, which operates by forcing senders to wait for a period before retrying. This can be effective for blocking spam sent through subpar SMTP engines. However, it faces compatibility issues when handling mail from large ISPs with SMTP clusters or non-RFC compliant mailservers that treat temporary delivery failure as a permanent one.
To use the maRBL project, users will need Net::Server::Multiplex, Net::RBLClient, Perl, and Postfix packages. This release features the ability to query p0f to selectively greylist clients based on their operating system.
Overall, the maRBL project has proven itself to be a reliable and efficient tool for filtering spam emails, providing flexibility and customizability to users.
However, RBLs can provide a simple and efficient solution to the problem. They are fast and reliable, but their effectiveness can be hindered by false positives. This is because RBL administrators need to be trusted to add and remove hosts accurately and in a timely manner. Unfortunately, many lists rely on humans to manage them, which can lead to errors and oversights. In some cases, lists may block entire IP ranges to put pressure on ISPs to address their spam problem.
Greylisting is another option, which operates by forcing senders to wait for a period before retrying. This can be effective for blocking spam sent through subpar SMTP engines. However, it faces compatibility issues when handling mail from large ISPs with SMTP clusters or non-RFC compliant mailservers that treat temporary delivery failure as a permanent one.
To use the maRBL project, users will need Net::Server::Multiplex, Net::RBLClient, Perl, and Postfix packages. This release features the ability to query p0f to selectively greylist clients based on their operating system.
Overall, the maRBL project has proven itself to be a reliable and efficient tool for filtering spam emails, providing flexibility and customizability to users.
What's New
Version 1.1: N/A