# 75行: 取消注释，设置mail.xxx.com
myhostname = mail.xxx.com
# 83行: 取消注释，设置xxx.com
mydomain = xxx.com
# 99行: 取消注释
myorigin = $mydomain
# 113行: 取消注释
inet_interfaces = all
# 116: 注释(注意是注释掉,因为113行已经取消了注释)
#inet_interfaces = localhost
# 119行: 推荐ipv4，如果支持ipv6，则可以为all
inet_protocols = ipv4
# 164行: 取消注释，设置localhost
mydestination = localhost
# 264行: 取消注释，指定内网和本地的IP地址范围
mynetworks = 127.0.0.0/8, 10.0.0.0/24
# 419行: 取消注释，邮件保存目录
home_mailbox = Maildir/
# 569行: 取消注释，修改
smtpd_banner = $myhostname ESMTP
# =======以下所有添加到最后尾部=======
# 规定邮件最大尺寸为10M message_size_limit = 10485760 # 规定收件箱最大容量为1G mailbox_size_limit = 1073741824 # SMTP认证 smtpd_sasl_type = dovecot smtpd_sasl_path = private/auth smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous smtpd_sasl_local_domain = $myhostname smtpd_recipient_restrictions = permit_mynetworks,permit_auth_destination,permit_sasl_authenticated,reject
原文：https://www.cnblogs.com/kaifayuan/p/11740887.html