Ubuntu 12.04安装配置Postfix dovecot cyrus sasl实例教程(mysql虚拟用户)。这里基于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_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。