John: > however, I had a similar problem a while back, Google would randomly > reject email for, to me, no good reason. > It turned out that with IPv6 postfix was not consistent in binding an > address for sending.
Please do not spread unnecessary confusion. If you had read this tread more carefully, then you would see that Google randomly rejects mail from the same site with correct PTR configuration. Here it is again: same message, same sender, same recipient, same SMTP client IP address, same SMTP server IP address. Nov 11 11:55:15 spike postfix/smtp[22958]: 3jcZv4004YzJrPw: to=<censored>, relay=aspmx.l.google.com[2607:f8b0:400d:c04::1a]:25, delay=3.6, delays=0.12/0.01/2.6/0.93, dsn=5.7.1, status=bounced (host aspmx.l.google.com[2607:f8b0:400d:c04::1a] said: 550-5.7.1 [2604:8d00:189::2] Our system has detected that this message does not 550-5.7.1 meet IPv6 sending guidelines regarding PTR records and authentication 550-5.7.1 . Please review 550-5.7.1 https://support.google.com/mail/?p=ipv6_authentication_error for more 550 5.7.1 information. l17si30149401qaj.81 - gsmtp (in reply to end of DATA command)) Nov 11 11:58:29 spike postfix/smtp[22980]: 3jcZyr2BpqzJrPw: to=<censored>, relay=aspmx.l.google.com[2607:f8b0:400d:c04::1a]:25, delay=1.4, delays=0.11/0.01/0.19/1.1, dsn=2.0.0, status=sent (250 2.0.0 OK 1415725109 k30si37581932qge.88 - gsmtp) Wietse
