1.遠端主機發送郵件
[[email protected] Desktop]# telnet 172.25.254.119 25
Trying 172.25.254.119…
Connected to 172.25.254.119.
Escape character is ‘^]’.
220 westos-mail.westos.com ESMTP Postfix
ehlo hello ##測試命令是否可識別
250-westos-mail.westos.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from:

[email protected] ##從[email protected]傳送
250 2.1.0 Ok
rcpt to:[email protected] ##發給[email protected]
250 2.1.5 Ok
data
354 End data with .
12qwaszx34erdfcv56tyghbn ##郵件內容
.
250 2.0.0 Ok: queued as 53E16EAC28

2.郵件客戶端訪問控制
[[email protected] ~]# postconf -e “smtpd_client_restrictions = check_client_access hash:/etc/postfix/access” ##配置smtpd_client_restrictions引數； 引號中的引數表示限制access檔案中記錄的使用者訪問 ； postconf -d | grep client執行該命令可找到該語句。
[

[email protected] ~]# vim /etc/postfix/access ##被限制的使用者ip記錄在該檔案中
172.25.254.219 REJECT ##限制172.25.254.219訪問
[[email protected] ~]# postmap /etc/postfix/access ##將該明文檔案加密
[[email protected] ~]# systemctl restart postfix.service
測試
[[email protected] ~]# telnet 172.25.254.119 25 ##遠端訪問
Trying 172.25.254.119…
Connected to 172.25.254.119.
Escape character is ‘^]’.
220 westos-mail.westos.com ESMTP Postfix
ehlo hello ##連結成功
250-westos-mail.westos.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from:

[email protected] ##設定郵件傳送端
250 2.1.0 Ok
rcpt to: [email protected] ##設定接受端
554 5.7.1 Client host rejected: Access denied ##訪問受限