我们通过 postfix 从我们的服务器发送邮件，并通过 return-path 捕获收件箱中的退回邮件。我们发现一种奇怪的情况，有时退回邮件被拒绝似乎直接发生在发送过程中，在这种情况下（似乎）我们的服务器充当中继，将退回邮件传递到退回收件箱。这很好——只是由于未设置发件人地址，因此外发电子邮件会失败。
所以我认为我们只需要在 postfix 中设置默认发件人地址的指导。但我不确定是否是这种情况。以下是编辑后的邮件服务器日志：
Feb 15 23:58:31 mydomain postfix/pickup[16622]: B469C261093: uid=33 from=<[email protected]>
Feb 15 23:58:31 mydomain postfix/cleanup[21945]: B469C261093: message-id=<[email protected]>
Feb 15 23:58:31 mydomain postfix/qmgr[15254]: B469C261093: from=<[email protected]>, size=62845, nrcpt=1 (queue active)
Feb 15 23:58:31 mydomain postfix/smtp[21947]: B469C261093: to=<[email protected]>, relay=aspmx.l.google.com[xx.xx.xx.xx]:25, delay=0.07, delays=0.01/0/0.04/0.02, dsn=5.1.1, status=bounced (host aspmx.l.google.com[xx.xx.xx.xx] said: 550-5.1.1 The email account that you tried to reach does not exist. Please try 550-5.1.1 double-checking the recipient's email address for typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1 https://support.google.com/mail/answer/6596 81si37032134qhz.3 - gsmtp (in reply to RCPT TO command))
Feb 15 23:58:31 mydomain postfix/cleanup[21945]: C752826109A: message-id=<[email protected]>
Feb 15 23:58:31 mydomain postfix/bounce[21948]: B469C261093: sender non-delivery notification: C752826109A
Feb 15 23:58:31 mydomain postfix/qmgr[15254]: C752826109A: from=<>, size=3121, nrcpt=1 (queue active)
Feb 15 23:58:31 mydomain postfix/qmgr[15254]: B469C261093: removed
Feb 15 23:58:37 mydomain postfix/smtp[21947]: C752826109A: host mail.mydomain.info[xx.xx.xx.xx] said: 451 Temporary local problem - please try later (in reply to end of DATA command)
Feb 15 23:58:39 mydomain postfix/smtp[21947]: C752826109A: to=<[email protected]>, relay=mx.something.com[xx.xx.xx.xx]:25, delay=7.5, delays=0/0/7.5/0.03, dsn=5.0.0, status=bounced (host mx.something.com[xx.xx.xx.xx] said: 550 <> Sender rejected. (in reply to MAIL FROM command))
Feb 15 23:58:39 mydomain postfix/qmgr[15254]: C752826109A: removed
有人可以提供如何设置发件人地址的指导吗？或者，如果这不是实际问题，可以提供一些见解吗？