Postfix

Nota

Probado en Fedora 30, Centos 7

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Servidor postfix

Instalación de postfix.

dnf install -y postfix dovecot

Editar archivo de configuración.

vim /etc/postfix/main.cf

# line 94 (75): uncomment and specify hostname
myhostname = mail.snicoper.local

# line 102 (83): uncomment and specify domain name
mydomain = snicoper.local

# line 118 (99): uncomment
myorigin = $mydomain

# line 132 (113): uncomment
inet_interfaces = all

# line 135 (116): comment
# inet_interfaces = localhost

# line 183 (164): comentar
#mydestination = $myhostname, localhost.$mydomain, localhost

# line 184 (165): descomentar
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain

# line 283 (264): uncomment and specify your LAN
mynetworks = 192.168.1.0/24, 127.0.0.0/8

# line 438 (419): uncomment (use Maildir)
home_mailbox = Maildir/

# line 593 (574): add
smtpd_banner = $myhostname ESMTP

# add at the last line

# limit an email size 10M
message_size_limit = 10485760

# limit mailbox 1G
mailbox_size_limit = 1073741824

# for SMTP-Auth settings
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous
smtpd_sasl_local_domain = $myhostname

# http://serverfault.com/questions/775415/postfix-noqueue-reject-rcpt-from-unknown
#smtpd_client_restrictions = permit_mynetworks,reject_unknown_client,permit
#smtpd_recipient_restrictions = permit_mynetworks,permit_auth_destination,permit_sasl_authenticated,reject
smtpd_recipient_restrictions = permit_sasl_authenticated, reject_unauth_destination
smtpd_sender_restrictions = reject_unknown_sender_domain

Dovecot

vim /etc/dovecot/dovecot.conf

# line 24: uncomment
protocols = imap pop3 lmtp submission

vim /etc/dovecot/conf.d/10-auth.conf

# line 10: uncomment and change ( allow plain text auth )
disable_plaintext_auth = no

# line 100: add 'login'
auth_mechanisms = plain login

vim /etc/dovecot/conf.d/10-mail.conf

# line 30: uncomment and add
mail_location = maildir:~/Maildir

vim /etc/dovecot/conf.d/10-master.conf

# line 107: uncomment and add

# Postfix smtp-auth
unix_listener /var/spool/postfix/private/auth {
    mode = 0666
    user = postfix # add
    group = postfix # add
}

vim /etc/aliases

# En la ultima linea agregar
root: snicoper

postalias /etc/aliases
newaliases

Importante

Ver Reglas SELinux

Para crear el certificado SSL, Crear SSL

vim /etc/postfix/main.cf

# add at the last line
# SSL
smtpd_use_tls = yes
smtpd_tls_cert_file = /etc/pki/tls/certs/snicoper.crt
smtpd_tls_key_file = /etc/pki/tls/certs/snicoper.key
smtpd_tls_session_cache_database = btree:/etc/postfix/smtpd_scache
# Centos 7
#smtpd_tls_session_cache_database = btree:/var/lib/postfix/smtpd_scache

vim /etc/postfix/master.cf

# Descomentar linea 29 (26)
smtps       inet   n       -       n       -       -       smtpd

# Descomentar lineas 30 (27) y 31 (28)
-o syslog_name=postfix/smtps
-o smtpd_tls_wrappermode=yes

vim /etc/dovecot/conf.d/10-ssl.conf

# line 8: uncomment
ssl = yes

# line 14,15: comentar
# line 16: añadir and specify certificate
ssl_cert = </etc/pki/tls/certs/snicoper.crt
ssl_key = </etc/pki/tls/certs/snicoper.key

systemctl start postfix.service
systemctl enable postfix.service
systemctl start dovecot.service
systemctl enable dovecot.service

Poner por defecto (si no lo esta) postfix

alternatives --config mta

Firewall

firewall-cmd --permanent --zone=public --add-service=smtp
firewall-cmd --reload

Lista de puertos por defecto

POP3 - port 110
IMAP - port 143
SMTP - port 25
HTTP - port 80
Secure SMTP (SSMTP) - port 465
Secure IMAP (IMAP4-SSL) - port 585
IMAP4 over SSL (IMAPS) - port 993
Secure POP3 (SSL-POP) - port 995