1. 域名解析：

   角色                        記錄類型                        主機記錄                        記錄值
   主域名                    A                                    @                                   104.225.233.249
   郵件域名                A                                     mail                                104.225.233.249
   郵件服務器             MX                                 @                                   mail.dollarphp.com
   反垃圾配置             TXT                                @                                  v=spf1 a mx ~al
    
   

   

2. 卸載sendmail：

   yum  -y  remove  sendmail

3. 安裝軟件：

   yum  -y  install  postfix  dovecot  cyrus-sasl-*  mailx

4. 配置postfix：
   vim /etc/postfix/main.cf

   queue_directory = /var/spool/postfix
   command_directory = /usr/sbin
   daemon_directory = /usr/libexec/postfix
   data_directory = /var/lib/postfix
   mail_owner = postfix
   myhostname = mail.dollarphp.com         #這裏要換成你自己的郵箱服務器
   mydomain = dollarphp.com                #這裏換成你自己的主機服務器
   myorigin = $mydomain
   inet_interfaces = all
   inet_protocols = ipv4
   mydestination = $myhostname, localhost.$mydomain, localhost,$mydomain,mail.$mydomain,www.$mydomain, ftp.$mydomain
   local_recipient_maps =
   unknown_local_recipient_reject_code = 550
   mynetworks = 0.0.0.0/0
   relay_domains = $mydestination
   alias_maps = hash:/etc/aliases
   alias_database = hash:/etc/aliases
   home_mailbox = Maildir/
   smtpd_banner = $myhostname ESMTP
   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
   sendmail_path = /usr/sbin/sendmail.postfix
   newaliases_path = /usr/bin/newaliases.postfix
   mailq_path = /usr/bin/mailq.postfix
   setgid_group = postdrop
   html_directory = no
   manpage_directory = /usr/share/man
   sample_directory = /usr/share/doc/postfix-2.10.1/samples
   readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES
   smtpd_sasl_auth_enable = yes
   smtpd_sasl_security_options = noanonymous
   broken_sasl_auth_clients = yes
   smtpd_recipient_restrictions = permit_sasl_authenticated,reject_unauth_destination,permit_mynetworks
   smtpd_client_restrictions = permit_sasl_authenticated
    
   

5. 配置dovecot：
   a. 配置監聽協議：
   vim /etc/dovecot/dovecot.conf

   protocols = imap pop3 lmtp
   listen = *
   dict {
   }
   !include conf.d/*.conf
   !include_try local.conf

   b. 配置登錄方式：
   vim /etc/dovecot/conf.d/10-auth.conf

   disable_plaintext_auth = no
   auth_mechanisms = plain login
   !include auth-system.conf.ext

   c. 配置郵件存儲位置：
   vim /etc/dovecot/conf.d/10-mail.conf

   mail_location = maildir:~/Maildir
   namespace inbox {
   inbox = yes
   }
   first_valid_uid = 1000
   mbox_write_locks = fcntl

   d. 配置ssl（關閉）：
   vim /etc/dovecot/conf.d/10-ssl.conf

   ssl = no
   ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
   ssl_key = </etc/pki/dovecot/private/dovecot.pem

6. 配置sasl2：
   a. 配置系統認證：
   vim /etc/sysconfig/saslauthd

   SOCKETDIR=/run/saslauthd
   MECH=shadow
   FLAGS=

   b. 配置登錄方式（創建新文件）：
   vim /usr/lib64/sasl2/smtpd.conf

   pwcheck_method: saslauthd
   mech_list: PLAIN LOGIN
   log_level:3

7. 添加用戶：

   useradd  dollarphp
   passwd  dollarphp

8. 啟動服務：

   systemctl  start  dovecot
   systemctl  start  postfix
   systemctl  start  saslauthd

9. 配置mailx：
   vim /etc/mail.rc

   set hold
   set append
   set ask
   set crt
   set dot
   set keep
   set emptybox
   set indentprefix="> "
   set quote
   set sendcharsets=iso-8859-1,utf-8
   set showname
   set showto
   set newmail=nopoll
   set autocollapse
   set markanswered
   ignore received in-reply-to message-id references
   ignore mime-version content-transfer-encoding
   fwdretain subject date from to
   set bsdcompat
   set [email protected]
   set smtp=mail.dollarphp.com
   set smtp-auth-user=adminmail
   set smtp-auth-password=123456
   set smtp-auth=login

10. 發送郵件：

    echo  "內容"  |  mail  -s  "標題"  [email protected]
    或
    mail  -s  "標題"  [email protected]  <  test.txt

    二、客戶端：

11. linux（接收）：
    a. 安裝telnet：

    yum  -y  install  telnet

    b. 登錄（dovecot的默認端口是110）：

    telnet  104.225.233.249  110

    c. 測試：
    
    d. 命令介紹：

    USER  xxx：輸入用戶名
    PASS  xxx：輸入密碼
    LIST：顯示信箱
    RETR n：打開第n封信

    e. 退出telnet：

    ctl+]
    quit

12. windows（發送+接收）：
    a. 安裝foxmail（官網：http://www.foxmail.com/）：
    
    b. 登錄：
    
    
    
    c. 測試：
    
    

centos7搭建郵件服務器postfix