On 11/22/20 3:54 PM, Henry S wrote:
Now I am trying to figure out how to configure mailman+postfix to pass the unnecessarily convoluted world of spam-free certification and ip blockings by those 'security lawmakers'.
Any suggestions on how to not be blocked by gmail, hotmail, etc? I have used DKIM (no signing yet), SPF, DMARC to no avail. Maybe not an appropriate question to this mailman list.
You need a fixed IP address and "full circle" aka "forward confirmed reverse DNS" <https://en.wikipedia.org/wiki/Forward-confirmed_reverse_DNS>.
You also need to DKIM sign your outgoing mail from your domain and publish an SPF record allowing your IP as a sender for your domain. I'm not sure, but publishing a DMARC policy, even if it's p=none is possibly helpful with some recipient domains.
Beyond that check your IP for blacklisting with a tool like <http://mxtoolbox.com/blacklists.aspx> and monitor your mail logs for blocked email and follow up with the blockers to get unblocked.
Things get better over time as your server develops a reputation.
-- Mark Sapiro <mark@msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan