我的 postfix 服务器遇到了一个奇怪的问题。我可以很好地发送和接收电子邮件，gmail 除外。每当我发送邮件到例如某人@gmail.com 时，它都会返回
I'm sorry to have to inform you that your message could not
be delivered [...]
The mail system
<someone@gmail.com>: user unknown
这就是我在 mail.log 中得到的
15:32 dovecot: imap-login: Login: user=<kontakt@minzkraut.com>, method=PLAIN, rip=37.120.177.241, lip=37.120.177.241, mpid=20955, TLS, session=<jaW3/4ZRAqsleLHx>
15:32 postfix/smtpd[20956]: connect from v22017054597548976.hotsrv.de[37.120.177.241]
15:32 postfix/smtpd[20956]: 4B34140DE2: client=v22017054597548976.hotsrv.de[37.120.177.241], sasl_method=PLAIN, sasl_username=kontakt@minzkraut.com
15:32 postfix/cleanup[20961]: 4B34140DE2: message-id=<592801bf80ad3c84cefbba9d68947b6a@minzkraut.com>
15:32 postfix/qmgr[17940]: 4B34140DE2: from=<kontakt@minzkraut.com>, size=1123, nrcpt=1 (queue active)
15:32 postfix/smtpd[20956]: disconnect from v22017054597548976.hotsrv.de[37.120.177.241]
15:32 spamd[17176]: spamd: connection from localhost [::1]:44313 to port 783, fd 5 …