二.配置MTA-postfix

1、安装postfix
安装postfix
shell
# yum install postfix
# rpm -e sendmail
2、配置postfix

shell
# postconf -n > /etc/postfix/main2.cf
# mv /etc/postfix/main.cf /etc/postfix/main.cf.old
# mv /etc/postfix/main2.cf /etc/postfix/main.cf
编辑main.cf：

shell
# vi /etc/postfix/main.cf
增加如下内容：


# hostname
mynetworks = 127.0.0.1
myhostname = mail.extmail.org
mydestination = $mynetworks $myhostname


# banner
mail_name = Postfix - by extmail.org
smtpd_banner = $myhostname ESMTP $mail_name


# response immediately
smtpd_error_sleep_time = 0s


# Message and return code control
message_size_limit = 5242880
mailbox_size_limit = 5242880
show_user_unknown_table_name = no


# Queue lifetime control
bounce_queue_lifetime = 1d
maximal_queue_lifetime = 1d
设置postfix开机自启：


shell
# chkconfig postfix on