Receive mails for errors

Support
1

Hello everyone.

When a user of yunohost/postfix try to send a mail, it is sometimes bounced with an error.

For example when the recipient address does not exist (error 550 5.2.0 mailbox unavailable.), the sender got a mail in his box about that.
But others errors codes are not notified to the sender.
For example these two error from Google ;

Jan 2 20:10:37 mail postfix/smtp[7983]: 7519E221A55: to=someone@gmail.com, relay=gmail-smtp-in.l.google.com[2a00:1450:400c:c06::1a]:25, delay=3.1, delays=1.2/0.12/0.17/1.6, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[2a00:1450:400c:c06::1a] said: 550-5.7.1 [2001:bc8:4400:2100::f:11] Our system has detected that this message 550-5.7.1 does not meet IPv6 sending guidelines regarding PTR records and 550-5.7.1 authentication. Please review 550-5.7.1 support.google.com/mail/?p=IPv6AuthError for more information 550 5.7.1 . lr1si74288038wjb.36 - gsmtp (in reply to end of DATA command))

Jan 3 00:19:49 mail postfix/smtp[11746]: 424B4220B94: host gmail-smtp-in.l.google.com[2a00:1450:400c:c06::1a] said: 421-4.7.0 [2001:bc8:4400:2100::f:11 15] Our system has detected an unusual 421-4.7.0 rate of unsolicited mail originating from your IP address. To protect 421-4.7.0 our users from spam, mail sent from your IP address has been 421-4.7.0 temporarily rate limited. Please visit 421-4.7.0 support.google.com/mail/?p=UnsolicitedRateLimitError to 421 4.7.0 review our Bulk Email Senders Guidelines. jd4si74921981wjb.273 - gsmtp (in reply to end of DATA command)

How can the sender be notified that his mail has not been delivered ?
And how the administrator or postmaster can be directly notified that his server has a problem without monitoring the logs ?

Thanks for your help if you have any idea.

2

Hi,

I’ve got exactly the same issue.
In fact, I think it is a matter of IPV6 PTR record, that does not exist for our IPV6 server’s address.

I’m going to ask my provider to create the required IPV6 PTR record, and hope it will solve this issue.

I’ll let you know if it works…

3

It seems I’ve found out a way to fix this issue.

https://productforums.google.com/forum/#!topic/gmail/K5klFKDnUAE

Just add the line:
inet_protocols = ipv4
to your /etc/postfix/main.cf file, and then restart postfix.

For the moment, it is working for me.

4

Thanks for your answers, but disabling IPv6 is not conceivable in 2018.
We must found another solution.