我将 postfix 设置为
command_directory = /usr/local/sbin
config_directory = /usr/local/etc/postfix
daemon_directory = /usr/local/libexec/postfix
data_directory = /var/db/postfix
debug_peer_level = 2
html_directory = /usr/local/share/doc/postfix
inet_interfaces = all
mail_owner = postfix
mailq_path = /usr/local/bin/mailq
manpage_directory = /usr/local/man
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain,
mydomain = abc.com.au
myhostname = cdb.au
myorigin = $mydomain
newaliases_path = /usr/local/bin/newaliases
queue_directory = /var/spool/postfix
readme_directory = /usr/local/share/doc/postfix
sample_directory = /usr/local/etc/postfix
sendmail_path = /usr/local/sbin/sendmail
setgid_group = maildrop
unknown_local_recipient_reject_code = 550
然后，我将用户添加到系统。当通过 Microsoft Outlook 发送邮件时，我收到错误，这是 /var/log/maillog 中的日志。
主机名 aaaaa 验证失败：未提供主机名或服务名，或者未知 11 月 1 日 16:59:47 cdb postfix/smtpd[14405]：从未知连接 [193.99.3.223]
答案1
这不是错误。这是通知。
它告诉您，您的主机名“aaaa”的 DNS 解析已损坏。您没有 IP 193.99.3.223 的 PTR，或者 193.99.3.223 的 PTR 与主机名“aaaa”不匹配。修复它，通知就会消失。
答案2
您搞混了 mydomain 和 myhostname。应该是这样的：
mydomain = com.au
myhostname = abc.cdb.au