在尝试通过CentOS 7上的postfix发送电子邮件时，看到以下错误消息，而我可以接收和下载没有看到任何错误的消息
postfix/smtpd[24532]: connect from unknown[5.31.230.96] postfix/smtpd[24532]: disconnect from unknown[5.31.230.96] 要么
postfix/smtpd[24366]: connect from unknown[5.31.230.96] postfix/smtpd[24366]: warning: Wrapper-mode request dropped from unknown[5.31.230.96] for service submission. TLS context initial...our logs. postfix/smtpd[24366]: disconnect from unknown[5.31.230.96] postfix/smtpd[24366]: connect from unknown[5.31.230.96] postfix/smtpd[24366]: warning: Wrapper-mode request dropped from unknown[5.31.230.96] for service submission. TLS context initial...our logs. postfix/smtpd[24366]: disconnect from unknown[5.31.230.96] postfix/smtpd[24369]: connect from unknown[5.31.183.32] postfix/smtpd[24369]: lost connection after EHLO from unknown[5.31.183.32] postfix/smtpd[24369]: disconnect from unknown[5.31.183.32]
要么
postfix/smtpd[24371]: connect from unknown[unknown] postfix/smtpd[24371]: lost connection after CONNECT from unknown[unknown] postfix/smtpd[24371]: disconnect from unknown[unknown]
后缀/ dovecotconfiguration按照文章https://www.rosehosting.com/blog/mailserver-with-virtual-users-and-domains-using-postfix-and-dovecot-on-a-centos-6-vps/