Hi Mohit, I run a niche email hosting company using Zimbra for B2B customers who are very sensitive to both spam and false positives. I used to spend a lot of time tweaking SpamAssassin but a few years ago started using commercial block list providers, which really cut down the amount of time I was forced to spend doing adjustments. Since I also do paid professional services, the extra time I had to do paid work more than offset the costs of the commercial block list providers. Plus, my customers are happier.
You don't say why you had a bad experience with commercial block list providers; that might be helpful for us to know. Anyway, I document what I do in a blog post: https://www.missioncriticalemail.com/2019/03/21/zimbra-anti-spam-best-practices-2019/ The post describes how we rely on several layers of protection (including those provided by Postfix, which I know you are not using), as well as our adjustments to Amavis and SpamAssassin. I hope there are some techniques in the blog post that will be helpful to you. With best regards, Mark _________________________________________________________________ L. Mark Stone, Founder North America's Leading Zimbra VAR/BSP/Training Partner For Companies With Mission-Critical Email Needs ----- Original Message ----- From: "mailop" <[email protected]> To: "mailop" <[email protected]> Sent: Thursday, October 14, 2021 5:20:55 PM Subject: [mailop] Fighting spam Hey All, I am sure this topic has come up in the past. I am wondering if anyone with more experience than me can comment on what they do to fight spam. I have a pretty basic and effective setup that I feel might become a little unmanageable in the future. I am using greylisting, SA, DCC, Razor and SPF filtering. (as I am still with qmail, I cant used DKIM) I am also using SA --ham on all users sent emails and SA --spam on a folder called LearnAsSpam SA --ham and SA --spam update the bayes score. I ask my customers to drop all spam emails (not newsletters and flyers) into the LearnAsSpam folder once in a while I also take emails from the LearnAsSpam folders, pick keywords and put them in my local.cf file for SA As my customer base increase, I want a more manageable solution. I donot want to use the 3rd party spam filtering service as I haven't had positive experiences with them. I would rather allow couple spam emails to slip through my filters than causing a plethora of problems when using the 3rd party spam filters. Please suggest. PS: I am aware that some one out there has written a patch for qmail to used DKIM, but I am about to move away from qmail and move to exim. I am seeing that the amount of time I spend on writing the rules of SA in taking up more and more time. _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
