> On 24.06.2023 at 19:38 John Levine via mailop wrote: > According to Gellner, Oliver via mailop <oliver.gell...@dm.de>: >> >>It matters if the greylisting takes place before or after RBL / domain >>reputation checks. If the greylisting comes first, I could imagine that the >>connections from most of those bots would have been blocked anyway (with a >>5xx response code).
> No, this is after DNSBL checks, which catch about 85% of attempted > connections. Those get, ah, special handling. >>and thereby introduces noticeable breakage into email communication. As >>a commercial ESP I wouldn’t set it up. It’s annoying for the users when >>they repeatedly have to wait for registration emails, order >>confirmation with payment details, when they are on the phone with >>someone and want to discuss a document, which just doesn’t arrive at >>the other end, and so on. Let alone cases where messages aren’t >>delivered at all, > That occasionally happens, but since I whitelist any /24 that has > successfully retried, it doesn't happen very much. I see, this looks like a better approach. Unfortunately many greylisting implementations only whitelist senders for a few days or even less. Or they fail to sync connections across different MTAs / regions. Example from the last hours (redacted): 2023-06-28 06:33 170.10.152.242 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 07:45 207.211.30.242 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 08:01 91.220.42.201 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 09:04 205.139.110.141 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 09:55 205.139.110.221 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 10:13 62.140.10.22 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 10:40 91.220.42.211 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 10:41 195.130.217.241 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 10:55 91.220.42.241 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' 2023-06-28 11:10 207.211.30.221 response: 4.1.0 451 'Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451' It goes on like this every day, all day long. The second attempt then succeeds, but this is just braindead. -- BR Oliver ________________________________ dmTECH GmbH Am dm-Platz 1, 76227 Karlsruhe * Postfach 10 02 34, 76232 Karlsruhe Telefon 0721 5592-2500 Telefax 0721 5592-2777 dmt...@dm.de<mailto:dmt...@dm.de> * www.dmTECH.de<http://www.dmtech.de> GmbH: Sitz Karlsruhe, Registergericht Mannheim, HRB 104927 Geschäftsführer: Christoph Werner, Martin Dallmeier, Roman Melcher ________________________________ Datenschutzrechtliche Informationen Wenn Sie mit uns in Kontakt treten, beispielsweise wenn Sie an unser ServiceCenter Fragen haben, bei uns einkaufen oder unser dialogicum in Karlsruhe besuchen, mit uns in einer geschäftlichen Verbindung stehen oder sich bei uns bewerben, verarbeiten wir personenbezogene Daten. Informationen unter anderem zu den konkreten Datenverarbeitungen, Löschfristen, Ihren Rechten sowie die Kontaktdaten unserer Datenschutzbeauftragten finden Sie hier<https://www.dm.de/datenschutzerklaerung-kommunikation-mit-externen-493832>. _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
