CentOS 7.9服务器迁移后Postfix/Dovecot多域名admin邮箱归集异常问题排查求助

最近我把服务器从CentOS 6.9迁移到了新的CentOS 7.9环境，过程中因为系统版本、Perl/Python/PHP/Apache的版本变化遇到了不少问题，好在都一一解决了。唯独Postfix和Dovecot这块一直让我头疼，至今没搞定。

具体问题是：发送到admin@domain1.com、admin@domain2.com、admin@domain3.com的邮件，全部都跑到服务器的admin账户里了，但这个admin账户根本没绑定任何域名，完全不是我想要的结果。

我已经尝试了以下操作，但都没有效果：

• 首先编辑了/etc/postfix/virtual文件，添加了如下映射：

  admin@domain1.com domain1.com-admin
  admin@domain2.com domain2.com-admin
  

  执行postmap /etc/postfix/virtual更新映射后，问题依旧。
• 接着我又编辑了/etc/postfix/vmailbox文件，添加了邮箱路径配置：

  admin@domain1.com domain1.com/admin
  admin@domain2.com domain2.com/admin
  

  同样执行了postmap /etc/postfix/vmailbox，但不同域名的admin邮件还是没有分开，依然归集到服务器admin账户。

我现在完全不知道该从哪里入手排查了，希望能得到一些指点。

以下是我的Postfix配置信息：

alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
debugger_command = PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin ddd $daemon_directory/$process_name $process_id & sleep 5
disable_vrfy_command = yes
header_checks = regexp:/etc/postfix/header_checks
home_mailbox = Maildir/
html_directory = no
inet_protocols = all
mailbox_command = /usr/bin/procmail-wrapper -o -a $DOMAIN -d $LOGNAME
mailbox_size_limit = 0
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
milter_default_action = accept
mydestination = $myhostname, $mydomain, localhost.$mydomain, localhost, mail.$mydomain
newaliases_path = /usr/bin/newaliases.postfix
non_smtpd_milters = inet:localhost:8891
readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES
resolve_dequoted_address = no
sample_directory = /usr/share/doc/postfix-2.10.1/samples
sender_bcc_maps = hash:/etc/postfix/bcc
sender_dependent_default_transport_maps = hash:/etc/postfix/dependent
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtp_tls_security_level = may
smtpd_error_sleep_time = 5s
smtpd_milters = inet:localhost:8891
smtpd_recipient_restrictions = permit_mynetworks permit_sasl_authenticated reject_unauth_destination
smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
smtpd_tls_CAfile = /etc/postfix/postfix.ca.pem
smtpd_tls_cert_file = /etc/postfix/postfix.cert.pem
smtpd_tls_key_file = /etc/postfix/postfix.key.pem
smtpd_tls_mandatory_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1
smtpd_tls_security_level = may
unknown_local_recipient_reject_code = 550
virtual_alias_maps = hash:/etc/postfix/virtual
virtual_mailbox_maps = hash:/etc/postfix/vmailbox

/etc/postfix/virtual文件片段：

domain1.com domain1.com
admin@domain1.com domain1.com-admin
domain2.com domain2.com
admin@domain2.com domain2.com-admin

/etc/postfix/vmailbox文件片段：

admin@domain1.com domain1.com/admin
admin@domain2.com domain2.com/admin

备注：内容来源于stack exchange，提问作者Wordsmith