$ grep reject.*github /var/log/mail/smtp.log [...] Jan 27 16:31:34 woodpecker postfix/smtpd[16778]: NOQUEUE: reject: RCPT from o6.sgmail.github.com[192.254.113.101]: 450 4.1.7 <bounces+848413-369f-patrick=gentoo.org@sgmail.github.com>: Sender address rejected: unverified address: connect to sgmail.github.com[167.89.125.30]:25: Connection refused; from=<bounces+848413-369f-patrick=gentoo.org@sgmail.github.com> to=<patrick@gentoo.org> proto=ESMTP helo=<o6.sgmail.github.com> Jan 27 16:45:09 woodpecker postfix/smtpd[8258]: NOQUEUE: reject: RCPT from o6.sgmail.github.com[192.254.113.101]: 450 4.1.7 <bounces+848413-369f-patrick=gentoo.org@sgmail.github.com>: Sender address rejected: unverified address: connect to sgmail.github.com[167.89.125.30]:25: Connection refused; from=<bounces+848413-369f-patrick=gentoo.org@sgmail.github.com> to=<patrick@gentoo.org> proto=ESMTP helo=<o6.sgmail.github.com> Jan 27 17:46:19 woodpecker postfix/smtpd[11107]: NOQUEUE: reject: RCPT from o5.sgmail.github.com[192.254.113.10]: 450 4.1.7 <bounces+848413-457f-grobian=gentoo.org@sgmail.github.com>: Sender address rejected: unverified address: connect to sgmail.github.com[167.89.125.30]:25: Connection refused; from=<bounces+848413-457f-grobian=gentoo.org@sgmail.github.com> to=<grobian@gentoo.org> proto=ESMTP helo=<o5.sgmail.github.com> Jan 27 17:53:23 woodpecker postfix/smtpd[15945]: NOQUEUE: reject: RCPT from o4.sgmail.github.com[192.254.112.99]: 450 4.1.7 <bounces+848413-457f-grobian=gentoo.org@sgmail.github.com>: Sender address rejected: unverified address: connect to sgmail.github.com[167.89.125.30]:25: Connection refused; from=<bounces+848413-457f-grobian=gentoo.org@sgmail.github.com> to=<grobian@gentoo.org> proto=ESMTP helo=<o4.sgmail.github.com> Happens pretty often. Probably because of their fancy sender addresses. Could someone please report that to their support? I really had enough of it.
Hopefully whitelisted now.
(In reply to Michał Górny from comment #1) > Hopefully whitelisted now. then close your bugs.