Linux系统下邮件服务器的搭建（Postfix+Dovecot+SSL）
系统环境为 centos7.2 x64 mini
1.首先安装编译环境包
yum install nginx vim gcc gcc-c++ openssl openssl-devel db4-devel ntpdate mysql mysql-devel mysql-server bzip2 php-mysql cyrus-sasl-md5 perl-GD perl-DBD-MySQL perl-GD perl-CPAN perl-CGI perl-CGI-Session cyrus-sasl-lib cyrus-sasl-plain cyrus-sasl cyrus-sasl-devel libtool-ltdl-devel telnet mail libicu-devel -y
2.开始编译安装postfix
a.创建相关用户
yum remove postfix -y userdel postfix groupdel postdrop groupadd -g 2525 postfix useradd -g postfix -u 2525 -s /sbin/nologin -M postfix groupadd -g 2526 postdrop useradd -g postdrop -u 2526 -s /sbin/nologin -M postdrop
b.编译安装
cd /usr/local/src/ wget ftp://ftp.cuhk.edu.hk/pub/packages/mail-server/postfix/official/postfix-3.3.1.tar.gz tar -zxvf postfix-3.3.1.tar.gz cd postfix-3.3.1 make makefiles 'CCARGS=-DHAS_MYSQL -I/usr/include/mysql -DUSE_SASL_AUTH -DUSE_CYRUS_SASL -I/usr/include/sasl -DUSE_TLS ' 'AUXLIBS=-L/usr/lib64/mysql -lmysqlclient -lz -lrt -lm -L/usr/lib64/sasl2 -lsasl2 -lssl -lcrypto' make && make install
在make install环节的时候会有个交互式的界面，可以自定义一些目录，根据自己的需求填写，本人这里只更改了第二项临时文件目录，其他的都选择了默认目录：
c. 更改授权
chown -R postfix:postdrop /var/spool/postfix chown -R postfix:postdrop /var/lib/postfix/ chown root /var/spool/postfix chown -R root /var/spool/postfix/pid
3. 配置 postfix
vi /etc/postfix/main.cf myhostname = mail.bt.dvcloud.xin mydomain = mail.bt.dvcloud.xin myorigin = $mydomain inet_interfaces = all # 推荐ipv4，如果支持ipv6，则可以为all inet_protocols = ipv4 mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain #mynetworks = 127.0.0.0/8, 10.0.0.0/24 home_mailbox = Maildir/ smtpd_banner = $myhostname ESMTP # 添加到最后 # 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
然后需要在/etc/init.d/目录下提供一个脚本来管理postfix的启动与停止
vim /etc/init.d/postfix
#!/bin/bash
#
# postfix Postfix Mail Transfer Agent
#
# chkconfig: 2345 80 30
# description: Postfix is a Mail Transport Agent, which is the program \
# that moves mail from one machine to another.
# processname: master
# pidfile: /var/spool/postfix/pid/master.pid
# config: /etc/postfix/main.cf
# config: /etc/postfix/master.cf
# Source function library.
. /etc/rc.d/init.d/functions
# Source networking configuration.
. /etc/sysconfig/network
# Check that networking is up.
[ $NETWORKING = "no" ] && exit 3
[ -x /usr/sbin/postfix ] || exit 4
[ -d /etc/postfix ] || exit 5
[ -d /var/spool/postfix ] || exit 6
RETVAL=0
prog="postfix"
start() {
# Start daemons.
echo -n $"Starting postfix: "
/usr/bin/newaliases >/dev/null 2>&1
/usr/sbin/postfix start 2>/dev/null 1>&2 && success || failure $"$prog start"
RETVAL=$?
[ $RETVAL -eq 0 ] && touch /var/lock/subsys/postfix
echo
return $RETVAL
}
stop() {
# Stop daemons.
echo -n $"Shutting down postfix: "
/usr/sbin/postfix stop 2>/dev/null 1>&2 && success || failure $"$prog stop"
RETVAL=$?
[ $RETVAL -eq 0 ] && rm -f /var/lock/subsys/postfix
echo
return $RETVAL
}
reload() {
echo -n $"Reloading postfix: "
/usr/sbin/postfix reload 2>/dev/null 1>&2 && success || failure $"$prog reload"
RETVAL=$?
echo
return $RETVAL
}
abort() {
/usr/sbin/postfix abort 2>/dev/null 1>&2 && success || failure $"$prog abort"
return $?
}
flush() {
/usr/sbin/postfix flush 2>/dev/null 1>&2 && success || failure $"$prog flush"
return $?
}
check() {
/usr/sbin/postfix check 2>/dev/null 1>&2 && success || failure $"$prog check"
return $?
}
restart() {
stop
start
}
# See how we were called.
case "$1" in
start)
start
;;
stop)
stop
;;
restart)
stop
start
;;
reload)
reload
;;
abort)
abort
;;
flush)
flush
;;
check)
check
;;
status)
status master
;;
condrestart)
[ -f /var/lock/subsys/postfix ] && restart || :
;;
*)
echo $"Usage: $0 {start|stop|restart|reload|abort|flush|check|status|condrestart}"
exit 1
esac
exit $?
设置该脚本权限
chmod +x /etc/init.d/postfix chkconfig --add postfix chkconfig postfix on chown postfix.postfix -R /var/lib/postfix/ chown postfix.postfix /var/spool/ -R
4.安装Dovecot
yum -y install dovecot
配置Dovecot
vi /etc/dovecot/dovecot.conf
# 如果不使用IPv6，请修改为* listen = *
vi /etc/dovecot/conf.d/10-auth.conf
disable_plaintext_auth = no auth_mechanisms = plain login
vi /etc/dovecot/conf.d/10-mail.conf
mail_location = maildir:~/Maildir
vi /etc/dovecot/conf.d/10-master.conf
# Postfix smtp验证
unix_listener /var/spool/postfix/private/auth {
mode = 0666
user = postfix
group = postfix
}
然后启动服务
/etc/init.d/postfix start systemctl start dovecot
测试：就可以使用Foxmail等第三方软件来收发邮件了。
系统用户就是邮件的用户，例如root，就是一个邮箱用户，邮箱是root@domain.com，密码就是root的密码，所以需要创建用户，只要使用useradd创建用户，再使用passwd设置密码。
好了，假如我们创建一个admin的用户：
# 创建用户 useradd nineven #设置密码，会要求输入两次密码 passwd nineven
第二章
配置SSL
1.创建自定义的ssl证书
cd /etc/pki/tls/certs make server.key umask 77 && /usr/bin/openssl genrsa -aes128 2048 > server.key
openssl rsa -in server.key -out server.key
make server.csr umask 77 && /usr/bin/openssl req -utf8 -new -key server.key -out server.csr
chmod 400 server.*
2.配置
vi /etc/postfix/main.cf
# 添加到最后
smtpd_use_tls = yes
smtpd_tls_cert_file = /etc/pki/tls/certs/server.crt
smtpd_tls_key_file = /etc/pki/tls/certs/server.key
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_tls_loglevel = 0
smtpd_tls_auth_only = yes
vi /etc/postfix/master.cf
smtps inet n - n - - smtpd -o smtpd_tls_wrappermode=yes
vi /etc/dovecot/conf.d/10-ssl.conf
ssl = yes # 指定证书 ssl_cert = </etc/pki/tls/certs/server.crt ssl_key = </etc/pki/tls/certs/server.key
然后重新启动服务
/etc/init.d/postfix restart systemctl restart dovecot
