Email server: Dovecot and Postfix

Fri, 20 Feb 2015 14:23:20 +0000

Postfix configuration

Install the required software:

$ yum install postfix postgrey dovecot fail2ban spamassassin 
spamass-milter-postfix opendkim

Create TLS certificate, key and CA authority (replace mail.domain.tld with a valid domain name):

$ mkdir /etc/postfix/ssl
$ cd /etc/postfix/ssl
$ openssl genrsa -aes256 -out mail.domain.tld.key 4096
$ chmod 600 mail.domain.tld.key
$ openssl req -sha256 -new -key mail.domain.tld.key -out mail.domain.tld.csr
$ openssl x509 -sha256 -req -days 1825 -in mail.domain.tld.csr -signkey mail.domain.tld.key -out mail.domain.tld.crt
$ openssl rsa -in mail.domain.tld.key -out mail.domain.tld.key.nopass
$ mv mail.domain.tld.key.nopass mail.domain.tld.key
$ openssl req -new -x509 -extensions v3_ca -keyout cakey.pem -out cacert.pem -days 3650 -sha256
$ chmod 600 mail.domain.tld.key
$ chmod 600 cakey.pem
$ openssl dhparam -out dhparams.pem 4096
$ chmod 600 dhparams.pem

Edit main.cf file accordingly (the other lines should be ok by default).
No SQL database is used, for user authentication postfix relies on Linux users, email data are stored in ~/Maildir.

Postfix on nagg.eu

Email server: Dovecot and Postfix

Postfix configuration