基本上配得差不多了，就是不能发信了
Sender address rejected: not owned by user
main.cf里面已经有了
smtpd_sender_login_maps =
mysql:/usr/local/etc/postfix/mysql_virtual_sender_maps.cf,
mysql:/usr/local/etc/postfix/mysql_virtual_alias_maps.cf
其中
mysql_virtual_sender_maps.cf内容如下
user = extmail
password = extmail
hosts = localhost
dbname = extmail
table = mailbox
select_field = username
where_field = username
additional_conditions = AND active = '1'
additional_conditions = AND smtp_limit = '1'
具体日志：
Oct 28 12:56:56 mail postfix/smtpd[798]: NOQUEUE: reject: RCPT from unknown[219.201.216.62]: 553 5.7.1 <
test@test.com>: Sender
address rejected: not owned by user
test@test.com; from=<
test@test.com> to=<
test@test.com> proto=ESMTP helo=<client>
