Instalación de servidor Postfix y Mysql
Requisitos previos:
Contar con un servidor LAMP previamente instalado y configurado, FQDN configurado y Mysql instalado y configurado.
Paso 1: Instalar los paquetes necesarios
user@server:$sudo apt-get install postfix postfix-mysql dovecot-core dovecot-imapd dovecot-pop3d dovecot-lmtpd dovecot-mysql
Paso 2: Crear la base de datos, tabla de dominios, usuarios y alias
mysqladmin -p create servermail
mysql -u root -p
mysql > GRANT SELECT ON servermail.* TO 'usermail'@'127.0.0.1' IDENTIFIED BY 'mailpassword';
mysql > FLUSH PRIVILEGES;
mysql> USE servermail;
CREATE TABLE `virtual_domains` (
`id` INT NOT NULL AUTO_INCREMENT,
`name` VARCHAR(50) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `virtual_users` (
`id` INT NOT NULL AUTO_INCREMENT,
`domain_id` INT NOT NULL,
`password` VARCHAR(106) NOT NULL,
`email` VARCHAR(120) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `email` (`email`),
FOREIGN KEY (domain_id) REFERENCES virtual_domains(id) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `virtual_aliases` (
`id` INT NOT NULL AUTO_INCREMENT,
`domain_id` INT NOT NULL,
`source` varchar(100) NOT NULL,
`destination` varchar(100) NOT NULL,
PRIMARY KEY (`id`),
FOREIGN KEY (domain_id) REFERENCES virtual_domains(id) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `servermail`.`virtual_domains`
(`id` ,`name`)
VALUES
('1', 'example.com'),
('2', 'hostname.example.com');
INSERT INTO `servermail`.`virtual_users`
(`id`, `domain_id`, `password` , `email`)
VALUES
('1', '1', ENCRYPT('firstpassword', CONCAT('$6$', SUBSTRING(SHA(RAND()), -16))), 'email1@example.com'),
('2', '1', ENCRYPT('secondpassword', CONCAT('$6$', SUBSTRING(SHA(RAND()), -16))), 'email2@example.com');
INSERT INTO `servermail`.`virtual_aliases`
(`id`, `domain_id`, `source`, `destination`)
VALUES
('1', '1', 'alias@example.com', 'email1@example.com');
mysql > exitPaso 3: Configuración de Postfix main.cf
Hasta el momento se ha tomado como referencia la guía publicada en digital ocean https://www.digitalocean.com/community/tutorials/how-to-configure-a-mail-server-using-postfix-dovecot-mysql-and-spamassassin, pero esta guía esta pensada para una versión de ubuntu muy antigua y no funciona en las versiones modernas, es por ello que le hice adaptaciones y el siguiente codigo del archivo de configuración es fruto de revisar muchos post y de aplicar el criterio sumado a varias pruebas de ensayo error. El código siguiente ha sido probado en ubuntu 16.04 y funciona a la perfección.
cp /etc/postfix/main.cf /etc/postfix/main.cf.orig
nano /etc/postfix/main.cf
# See /usr/share/postfix/main.cf.dist for a commented, more complete version
# Debian specific: Specifying a file name will cause the first
# line of that file to be used as the name. The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname
smtpd_banner = $myhostname ESMTP $mail_name (ubuntu)
biff = no
# appending .domain is the MUA's job.
append_dot_mydomain = no
# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h
readme_directory = no
# TLS parameters
#smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
#smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
#smtpd_use_tls=yes
#smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
#smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
#agregar estas dos lineas
smtpd_tls_security_level = may
smtp_tls_security_level = may
#smtpd_tls_cert_file=/etc/dovecot/dovecot.pem
#smtpd_tls_key_file=/etc/dovecot/private/dovecot.pem
smtpd_tls_cert_file = /etc/letsencrypt/live/enappserver.com/cert.pem
smtpd_tls_key_file = /etc/letsencrypt/live/enappserver.com/privkey.pem
smtpd_tls_CAfile = /etc/letsencrypt/live/enappserver.com/chain.pem
smtpd_use_tls=yes
#smtp_use_tls = yes
smtpd_tls_auth_only = yes
smtp_tls_note_starttls_offer = yes
#agregar otras 2 lineas
smtpd_tls_received_header = yes
smtpd_tls_loglevel = 1
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain =
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions =
permit_sasl_authenticated,
permit_mynetworks,
reject_unauth_destination
# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.
#smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
myhostname = mail.enappserver.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = localhost
relayhost =
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
message_size_limit = 0
virtual_mailbox_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all
strict_mailbox_ownership = no
virtual_transport = lmtp:unix:private/dovecot-lmtp
virtual_mailbox_domains = mysql:/etc/postfix/mysql-virtual-mailbox-domains.cf
virtual_mailbox_maps = mysql:/etc/postfix/mysql-virtual-mailbox-maps.cf
virtual_alias_maps = mysql:/etc/postfix/mysql-virtual-alias-maps.cf
#OpenDKIM
milter_default_action = accept
milter_protocol = 2
smtpd_milters = inet:localhost:8891
#smtpd_milters = inet:8891@localhost
non_smtpd_milters = inet:localhost:8891
#controlar el reintento de correos no enviados
maximal_queue_lifetime = 3h
queue_run_delay = 300s
minimal_backoff_time = 300s
maximal_backoff_time = 4000s
Lo siguiente es crear y configurar los archivos necesarios para conectar postfix con la base de datos mysql y las tablas ya creadas
nano /etc/postfix/mysql-virtual-mailbox-domains.cf
user = usermail
password = mailpassword
hosts = 127.0.0.1
dbname = servermail
query = SELECT 1 FROM virtual_domains WHERE name='%s'
nano /etc/postfix/mysql-virtual-mailbox-maps.cf
user = usermail
password = mailpassword
hosts = 127.0.0.1
dbname = servermail
query = SELECT 1 FROM virtual_users WHERE email='%s'
nano /etc/postfix/mysql-virtual-alias-maps.cf
user = usermail
password = mailpassword
hosts = 127.0.0.1
dbname = servermail
query = SELECT destination FROM virtual_aliases WHERE source='%s'Finalmente reiniciamos el servicio de postfix y probamos la configuracion de los tres archivos. Deberíamos obtener un 1 en cada caso.
service postfix restart
postmap -q example.com mysql:/etc/postfix/mysql-virtual-mailbox-domains.cf
postmap -q email1@example.com mysql:/etc/postfix/mysql-virtual-mailbox-maps.cf
postmap -q alias@example.com mysql:/etc/postfix/mysql-virtual-alias-maps.cfCopiamos el archivo de configuracion master.cf
cp /etc/postfix/master.cf /etc/postfix/master.cf.orig
Editamos el archivo master.cf
nano /etc/postfix/master.cfEl código debería quedar así:
smtp inet n - - - - smtpd
submission inet n - - - - smtpd
-o syslog_name=postfix/submission
smtps inet n - - - - smtpd
-o syslog_name=postfix/smtps
-o smtpd_tls_wrappermode=yes
-o smtpd_sasl_auth_enable=yes
-o smtpd_client_restrictions=permit_sasl_authenticated,reject
-o milter_macro_daemon_name=ORIGINATING
-o smtpd_tls_security_level=encrypt
-o smtpd_relay_restrictions=permit_mynetworks,permit_sasl_authenticate,reject
-o smtpd_client_restrictions=
-o smtpd_helo_restrictions=
-o smtpd_sender_restrictions=
-o smtpd_recipient_restrictions=
-o smtpd_data_restrictions=
-o smtpd_end_of_data_restrictions=
pickup unix n - - 60 1 pickup
cleanup unix n - - - 0 cleanup
qmgr unix n - n 300 1 qmgr
tlsmgr unix - - - 1000? 1 tlsmgr
rewrite unix - - - - - trivial-rewrite
bounce unix - - - - 0 bounce
defer unix - - - - 0 bounce
trace unix - - - - 0 bounce
verify unix - - - - 1 verify
flush unix n - - 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - - - - smtp
relay unix - - - - - smtp
showq unix n - - - - showq
error unix - - - - - error
retry unix - - - - - error
discard unix - - - - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - - - - lmtp
anvil unix - - - - 1 anvil
scache unix - - - - 1 scache
maildrop unix - n n - - pipe
flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
${user}
${user}
uucp unix - n n - - pipe
flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
ifmail unix - n n - - pipe
flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp unix - n n - - pipe
flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient
scalemail-backend unix - n n - 2 pipe
flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} $$
mailman unix - n n - - pipe
flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
${nexthop} ${user}