Got it, on mx2 -
2023-12-01T16:20:57.371629+00:00 mx2 postfix/smtp[24055]: F368B7417: to=<arvidjaar@gmail.com>, relay=gmail-smtp-in.l.google.com[2a00:1450:400c:c0b::1b]:25, delay=0.37, delays=0.01/0/0.13/0.23, dsn=5.7.26, status=bounced (host gmail-smtp-in.l.google.com[2a00:1450:400c:c0b::1b] said: 550-5.7.26 This mail has been blocked because the sender is unauthenticated. 550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM. 550-5.7.26 550-5.7.26 Authentication results: 550-5.7.26 DKIM = did not pass 550-5.7.26 SPF [opensuse.org] with ip: [2a07:de40:b27e:1209::12] = did not pass 550-5.7.26 550-5.7.26 To mitigate this issue, please visit Gmail's authentication guide 550-5.7.26 for instructions on setting up authentication: 550 5.7.26 https://support.google.com/mail/answer/81126#authentication g11-20020adff3cb000000b003316e398704si2029809wrp.884 - gsmtp (in reply to end of DATA command))
550-5.7.26 This mail has been blocked because the sender is unauthenticated.
550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM.
550-5.7.26
550-5.7.26 Authentication results:
550-5.7.26 DKIM = did not pass
550-5.7.26 SPF [opensuse.org] with ip: [2a07:de40:b27e:1209::12] = did not pass
550-5.7.26
550-5.7.26 To mitigate this issue, please visit Gmail's authentication guide
550-5.7.26 for instructions on setting up authentication:
550 5.7.26 https://support.google.com/mail/answer/81126#authentication
This was on 1 December, and similar can be seen in logs up until 4 December, then it stops - were we perhaps late with updating the SPF record?
Interestingly, on 3 December, Google changes their response:
421-4.7.26 This mail has been rate limited because it is unauthenticated. Gmail
421-4.7.26 requires all senders to authenticate with either SPF or DKIM.
421-4.7.26
421-4.7.26 Authentication results:
421-4.7.26 DKIM = did not pass
421-4.7.26 SPF [opensuse.org] with ip: [2a07:de40:b27e:1209::12] = did not pass
421-4.7.26
421-4.7.26 To mitigate this issue, please visit Gmail's authentication guide
421-4.7.26 for instructions on setting up authentication:
421 4.7.26 https://support.google.com/mail/answer/81126#authentication
Also interesting - perhaps - we have been sending thousands of mails to gmail addresses, no problem, throughout November and December. I don't really understand why some were bounced, others delayed, and a lot were let through.
Andrey, I have re-enabled delivery from the factory and the support list.