On Jul 22, 2024, at 4:21 PM, Wietse Venema via Postfix-users <postfix-users@postfix.org> wrote: > > Austin Witmer via Postfix-users: >> Hello all! >> >> I recently added mlmmj as a mailing list manager to my postfix server. >> >> My concern is that I don't overwhelm the big boys (yahoo, google, >> iCloud) and have them rate limit me because I am sending to too >> many addresses to quickly. >> >> Here are my transport settings for mlmmj. >> >> mlmmj_destination_concurrency_limit = 5 >> mlmmj_destination_concurrency_failed_cohort_limit = 10 >> mlmmj_destination_rate_delay = 1s >> mlmmj_destination_recipient_limit = 1 > > Caution: with mlmmj_destination_recipient_limit=1, the unit of > concurrency is the recipient address, not the domain name. Postfix > will deliver up to 5 recipients in parallel assuming that your SMTP > client process limit is 5 or more. > >> Are they sensible? Am I being overly cautious? Any suggestions for >> improvement? I have one mailing list I am setting up with over >> 1500 subscribers and so I want to get this right. > > You will need SPF, DKIM, and DMARC with 'p=reject'. If this is > an interactive list, you will need to replace list member's From: > headers with your mailing list address to satisfy DMARC.
I believe I have SPF, DKIM and DMARC setup with p=reject. So the big list with 1500 members is not an interactive list and probably will just have one sending (gmail) address. Will DMARC be broken if I only add the following headers to mailing list messages? X-Mailinglist: List-Id: List-Unsubscribe: List-Unsubscribe-Post: From what I was reading online, I thought “From munging” is not necessary if I am not modifying the subject, body or existing email headers. And thus the original senders DMARC won’t be broken, right? Or is adding the headers I mentioned above modifying the message enough to break DMARC as well? > > You will need to start slow, and increase delivery rates in the course > of ~weeks. > > Wietse > _______________________________________________ > Postfix-users mailing list -- postfix-users@postfix.org > To unsubscribe send an email to postfix-users-le...@postfix.org _______________________________________________ Postfix-users mailing list -- postfix-users@postfix.org To unsubscribe send an email to postfix-users-le...@postfix.org
