本文是基于ubuntu 12.04配置的邮件服务器，利用postfix提供邮件smtp服务，dovecot提供pop3或imap代理收信服务。使用mysql管理和验证邮件用户。以下操作经本人亲试通过，涉及域名centos.bz的请替换为自己的。

一、安装必要包

apt-get install postfix postfix-mysql postfix-doc mysql-client mysql-server dovecot-common dovecot-imapd dovecot-pop3d libsasl2-2 libsasl2-modules libsasl2-modules-sql sasl2-bin libpam-mysql openssl telnet mailutils dovecot-mysql

二、设置MySQL数据库

mysql -u root -p

mysql> CREATE DATABASE mail;

mysql> USE mail;

mysql> GRANT SELECT, INSERT, UPDATE, DELETE ON mail.* TO 'mail_admin'@'localhost' IDENTIFIED BY 'password-for-mail_admin';

mysql> GRANT SELECT, INSERT, UPDATE, DELETE ON mail.* TO 'mail_admin'@'127.0.0.1' IDENTIFIED BY 'password-for-mail_admin';

mysql> FLUSH PRIVILEGES;

mysql> CREATE TABLE domains (domain varchar(50) NOT NULL, PRIMARY KEY (domain) );

mysql> CREATE TABLE forwardings (source varchar(80) NOT NULL, destination TEXT NOT NULL, PRIMARY KEY (source) );

mysql> CREATE TABLE users (email varchar(80) NOT NULL, password varchar(20) NOT NULL, PRIMARY KEY (email) );

mysql> CREATE TABLE transport ( domain varchar(128) NOT NULL default '', transport varchar(128) NOT NULL default '', UNIQUE KEY domain (domain) );

mysql> quit

注：请替换password-for-mail_admin为用户mail_admin的密码，以下出现password-for-mail_admin的也请替换下。

三、配置Postfix使用MySQL

文件：/etc/postfix/mysql-virtual_domains.cf

user = mail_admin

password = password-for-mail_admin

dbname = mail

query = SELECT domain AS virtual FROM domains WHERE domain='%s'

hosts = 127.0.0.1

文件：/etc/postfix/mysql-virtual_forwardings.cf

user = mail_admin

password = password-for-mail_admin

dbname = mail

query = SELECT destination FROM forwardings WHERE source='%s'

hosts = 127.0.0.1

文件：/etc/postfix/mysql-virtual_mailboxes.cf

user = mail_admin

password = password-for-mail_admin

dbname = mail

query = SELECT CONCAT(SUBSTRING_INDEX(email,'@',-1),'/',SUBSTRING_INDEX(email,'@',1),'/') FROM users WHERE email='%s'

hosts = 127.0.0.1

文件：/etc/postfix/mysql-virtual_email2email.cf

user = mail_admin

password = password-for-mail_admin

dbname = mail

query = SELECT email FROM users WHERE email='%s'

hosts = 127.0.0.1

设置权限：

chmod o= /etc/postfix/mysql-virtual_*.cf

chgrp postfix /etc/postfix/mysql-virtual_*.cf

建立用户：

groupadd -g 5000 vmail

useradd -g vmail -u 5000 vmail -d /home/vmail -m

配置postfix:

postconf -e 'myhostname = centos.bz'

postconf -e 'mydestination = centos.bz, localhost, localhost.localdomain'

postconf -e 'mynetworks = 127.0.0.0/8'

postconf -e 'message_size_limit = 30720000'

postconf -e 'virtual_alias_domains ='

postconf -e 'virtual_alias_maps = proxy:mysql:/etc/postfix/mysql-virtual_forwardings.cf, mysql:/etc/postfix/mysql-virtual_email2email.cf'

postconf -e 'virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql-virtual_domains.cf'

postconf -e 'virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql-virtual_mailboxes.cf'

postconf -e 'virtual_mailbox_base = /home/vmail'

postconf -e 'virtual_uid_maps = static:5000'

postconf -e 'virtual_gid_maps = static:5000'

postconf -e 'smtpd_sasl_auth_enable = yes'

postconf -e 'broken_sasl_auth_clients = yes'

postconf -e 'smtpd_sasl_authenticated_header = yes'

postconf -e 'smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination'

postconf -e 'smtpd_use_tls = yes'

postconf -e 'smtpd_tls_cert_file = /etc/postfix/smtpd.cert'

postconf -e 'smtpd_tls_key_file = /etc/postfix/smtpd.key'

postconf -e 'proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps $recipient_canonical_maps $relocated_maps $transport_maps $mynetworks $virtual_mailbox_limit_maps'

postconf -e 'virtual_transport = dovecot'

postconf -e 'local_transport = dovecot'

四、为postfix创建证书：

cd /etc/postfix

openssl req -new -outform PEM -out smtpd.cert -newkey rsa:2048 -nodes -keyout smtpd.key -keyform PEM -days 365 -x509

更改证书权限：

chmod o= /etc/postfix/smtpd.key

五、配置saslauthd

mkdir -p /var/spool/postfix/var/run/saslauthd

cp -a /etc/default/saslauthd /etc/default/saslauthd.bak

编辑文件：/etc/default/saslauthd，按以下内容修改：

START=yes

DESC="SASL Authentication Daemon"

NAME="saslauthd"

MECHANISMS="pam"

MECH_OPTIONS=""

THREADS=5

OPTIONS="-c -m /var/spool/postfix/var/run/saslauthd -r"

文件：/etc/pam.d/smtp

auth    required   pam_mysql.so user=mail_admin passwd=password-for-mail_admin host=127.0.0.1 db=mail table=users usercolumn=email passwdcolumn=password crypt=1

account sufficient pam_mysql.so user=mail_admin passwd=password-for-mail_admin host=127.0.0.1 db=mail table=users usercolumn=email passwdcolumn=password crypt=1

文件：/etc/postfix/sasl/smtpd.conf

pwcheck_method: saslauthd

mech_list: plain login

allow_plaintext: true

auxprop_plugin: sql

sql_engine: mysql

sql_hostnames: 127.0.0.1

sql_user: mail_admin

sql_passwd: password-for-mail_admin

sql_database: mail

sql_select: select password from users where email = '%u@%r'

设置权限：

chmod o= /etc/pam.d/smtp

chmod o= /etc/postfix/sasl/smtpd.conf

重启服务：

adduser postfix sasl

service postfix restart

service saslauthd restart

六、配置Dovecot

文件：/etc/postfix/master.cf，按如下修改

取消submission配置的注释：

#submission inet n       -       -       -       -       smtpd

#  -o syslog_name=postfix/submission

#  -o smtpd_tls_security_level=encrypt

#  -o smtpd_sasl_auth_enable=yes

#  -o smtpd_client_restrictions=permit_sasl_authenticated,reject

#  -o milter_macro_daemon_name=ORIGINATING

 改为

submission inet n       -       -       -       -       smtpd

  -o syslog_name=postfix/submission

  -o smtpd_tls_security_level=encrypt

  -o smtpd_sasl_auth_enable=yes

  -o smtpd_client_restrictions=permit_sasl_authenticated,reject

  -o milter_macro_daemon_name=ORIGINATING

文件尾增加：

dovecot   unix  -       n       n       -       -       pipe

    flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -d ${recipient}

cp -a /etc/dovecot/dovecot.conf /etc/dovecot/dovecot.conf.bak

清空文件/etc/dovecot/dovecot.conf，加入如下：

log_timestamp = "%Y-%m-%d %H:%M:%S "

mail_location = maildir:/home/vmail/%d/%n/Maildir

namespace {

  inbox = yes

  location =

  prefix = INBOX.

  separator = .

  type = private

}

passdb {

  args = /etc/dovecot/dovecot-sql.conf

  driver = sql

}

protocols = imap pop3

disable_plaintext_auth = no

auth_mechanisms = plain login

service auth {

  unix_listener /var/spool/postfix/private/auth {

    group = postfix

    mode = 0660

    user = postfix

  }

  unix_listener auth-master {

    mode = 0600

    user = vmail

  }

  user = root

}

#ssl = required

ssl=yes

ssl_cert = </etc/ssl/certs/dovecot.pem

ssl_key = </etc/ssl/private/dovecot.pem

userdb {

  args = uid=5000 gid=5000 home=/home/vmail/%d/%n allow_all_users=yes

  driver = static

}

protocol lda {

  auth_socket_path = /var/run/dovecot/auth-master

  log_path = /home/vmail/dovecot-deliver.log

  postmaster_address = postmaster@example.com

}

protocol pop3 {

  pop3_uidl_format = %08Xu%08Xv

}

cp -a /etc/dovecot/dovecot-sql.conf /etc/dovecot/dovecot-sql.conf.bak

文件：/etc/dovecot/dovecot-sql.conf

driver = mysql

connect = host=127.0.0.1 dbname=mail user=mail_admin password=password-for-mail_admin

default_pass_scheme = CRYPT

password_query = SELECT email as user, password FROM users WHERE email='%u';

service dovecot restart

 

 

chgrp vmail /etc/dovecot/dovecot.conf

chmod g+r /etc/dovecot/dovecot.conf

七、设置Mail Aliases

文件/etc/aliases

postmaster: root

root: postmaster@centos.bz

八、测试

mysql -u root -p

USE mail;

INSERT INTO domains (domain) VALUES ('centos.bz');

INSERT INTO users (email, password) VALUES ('sales@centos.bz', ENCRYPT('password-for-sales'));

quit

这里添加了一个sales@centos.bz的用户，密码为password-for-sales

最后，可以使用邮件客户端，如foxmail进行收信和发信的测试。