El jue, 3 dic 2020 a las 17:59, Wietse Venema (<wie...@porcupine.org>) escribió:
> > So, the complete error message would be : > > > > "I made DNS queries with type A and AAAA for the name > > another-example.com.mail.protection.outlook.com. All queries > > failed. The last query that failed had type AAAA. The last error > > was "name exists but there is no AAAA record". > > > > But we reall don't want to send THAT in an email bounce message. > > > > > I wonder if beyond this bouncing the smtp uses then IPv4 and sends the > > > messages anyway. Please could you clarify this for me? > > > > All A and AAAA queries failed. > > Sergio Belkin: > > > > Thanks Wietse for your answer > > > > Is quite interesting that I find the following in logs: > > Dec 2 23:53:09 muteriver postfix/smtp[28063]: warning: no MX host for > > another-example.com has a valid address record > > Indeed, these details are not revealed in the bounce message but > can be found in Postfix logs. > > > And then: > > > > Dec 2 23:53:09 muteriver postfix/smtp[28063]: ED1CF1813C56F: to=< > > apere...@another-example.com>, relay=none, delay=5.9, > delays=0.17/0/5.8/0, > > dsn=5.4.4, status=bounced (Host or domain name not found. Name service > > error for name=another-example.com.mail.protection.outlook.com > type=AAAA: > > Host found but no data record of requested type) > > > > and finally: > > > > Dec 2 23:53:10 muteriver postfix/qmgr[1528]: ED1CF1813C56F: removed > > > > That last line led me to wonder if the message was finally sent... > > The message ED1CF1813C56F is deleted ONLY after Postfix successfully > injects the non-delivery notifcation into the Postfix mail queue. > > > If I try to resolve another-example.com.mail.protection.outlook.com > > manually on the mail server works fine with IPv4. > > > > What do you think? > > What comes to mind: > > 1) You ran the command as root, and the Postfix SMTP client does > not run as root. Name resution fails when the necessary files are > not accessible. > > 2) You ran the command outside the Postfix chroot jail, and the > Postfix SMTP client runs inside the Postfix chroot jail. Name > resolution fails inside the chroot jail when files are missing, > have wrong permissions, or have wrong contents. > > 3) Some "security" configuration is breaking Postfix. For exammple > SeLiux or AppArmor. > I have SELinux disables, and have no AppArmor > > 4) Some other permisssion or configuration problem. > It's weird because it only happens with a few domains... > > To find out if name resolution fails due to missing files or bad > permissions, run the Postfix SMTP client under strace as described > in http://www.postfix.org/DEBUG_README.html > > Wietse > Thanks -- -- Sergio Belkin LPIC-2 Certified - http://www.lpi.org
