Postfix spam prevention with simple means

I've published already quite a few tutorials on greylisting, rbls and so on. Here's another tutorial showing how you can reduce your spam with rather simple means. First of all we need to edit the file /etc/postfix/ and add those lines: smtpd_helo_required     = yes strict_rfc821_envelopes = yes disable_vrfy_command = yes unknown_address_reject_code  = 554 […]

Integrating Postgrey into Postfix (Greylisting Filter)

In this article I'm going to show the simple integration of Postgrey into a postfix. The installation of postgrey is done like this: apt-get install postgrey Then you should (but it's not needed) customize a little bit its configuration file /etc/default/postgrey, which contains: POSTGREY_OPTS="–inet=" #Postgrey uses the port 60000 locally POSTGREY_TEXT="Greylisted" #This parameter is optional […]

Greylisting with Postfix

Greylisting is an effective method of reducing spam. There's a daemon called GLD which is quite easy to integrate into Postfix. If you do not have your Postfix installation running, checkout for my other howto's. Installation of the needed package: apt-get install postfix-gld For the service to really start, you need to modify the file /etc/default/gld and […]

Realtime Blackhole Lists in Postfix

Realtime Blackhole Lists (RBL’s) are services that are keeping track of IP addresses from which spam or malware has been received. Cross-checking your incoming mails with one or more services may reduce your spam. Some known RBL’s are fpr example or To integrate them in Postfix, you just have to add the following […]