Hi all, I have check_recipient_mx_access setup to route mail for certain providers through a relay. This has been working well, until I discovered it is breaking delivery to local users that get CC'd in an email that is being routed through this relay.
Here is how I have it setup: smtpd_recipient_restrictions = check_recipient_mx_access hash:/etc/postfix/mxrelay permit_mynetworks permit_sasl_authenticated check_client_access hash:/etc/postfix/rbl_override reject_rbl_client b.barracudacentral.org reject_rbl_client zen.spamhaus.org check_policy_service unix:/var/spool/postfix/postgrey/socket [root@main log]# cat /etc/postfix/mxrelay outlook.com FILTER relay:[in-v3.mailjet.com]:587 prodigy.net FILTER relay:[in-v3.mailjet.com]:587 yahoodns.net FILTER relay:[in-v3.mailjet.com]:587 google.com FILTER relay:[in-v3.mailjet.com]:587 If an email gets sent where the "To" address triggers the relay, and a local user is CC'd in the email, the CC for the local user *also* gets sent through the relay, and the address is mangled. Here's what I mean by this, here's an example log line for a local user that should have been delivered directly, getting sent through the relay. Note that the "to" address has been mangled to a local user delivery address. This of course ends up being blocked/bounced on the relay side: Jun 9 18:12:27 main postfix/smtp[24065]: B31CEC37: to=< russell-example....@main.example.com>, orig_to=<russ...@example.com>, relay= in-v3.mailjet.com[104.199.96.85]:587, delay=1.9, delays=0.15/0.01/1.5/0.28, dsn=2.0.0, status=sent (250 OK queued as 49cd4c02-9c27-4d9d-958f-1a5ef2a64c24) How can I do MX filtering and relaying, while telling Postfix to never send a local domain through the relay? Thank you for the help!
