>-----Original Message----- >From: mailop <[email protected]> On Behalf Of Boris Mutina via mailop >Sent: Monday, August 10, 2026 7:20 AM >To: [email protected] >Subject: [mailop] Greylisting practices > >Hello, >need advice about greylisting practices. Here's the scenario:
I use postfix as my MTA with it's after 220 checks, which effectively is greylisting. The problem you encounter is the big guys, google, sendgrid, etc, do have farms of servers handing their mail. So the first temp reject from you goes to them and they properly retry later. And postfix (or whatever greylist tool you are using) records who it rejected from. A few minutes later the server farm retries, from a different IP this time so it gets temp rejected again, and so on. So yes, it's a problem. I use a tool called postallow (a newer fork of postwhite) to whitelist these desirable senders, it basically takes the domain and scrapes their SPF data to now all the servers they say are OK to send from. Do you get a lot of crap in there you don't want, probably. But you still whack all the zillion bots. _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
