Learning System You are able to additionally tune SpamAssassin to learn about your email.  Two programs are used together to create this learning system; autowhitelisting and Bayesian filtering.  Autowhitelisting is an algorithm that learns about each senders history and modifies the spam score of their subsequent mail.  This should ...

Sometimes when you are working with Postfix you may be on an older version that does not support a feature you need.  Here is a list of the version and the major features that were added for that version. Postfix 2.5 Stress-dependent configuration Postfix 2.3 DKIM, DomainKeys and SenderID authentication, DSN status notifications, Enhanced status codes, Plug-in support for multiple SASL implementations (Cyrus, Dovecot), Configurable delivery status ...

Reducing Syslogd Performance Issues Syslogd is the main logging program for many Linux systems.  Unfortunately it can cause performance issues by using synchronous writes by default.  If you open syslog.conf you will see that the mail logging goes to /var/log/mail.log.  In order to prevent synchronous writes a "-" is placed in front of the log. mail.*                          -/var/log/mail.log This is a default on most ...

Thunderbird, Icedove if you are on Debian is an excellent choice for an email client especially as it is capable of connecting using SSL or TLS and SMTP AUTH.  Many email clients are not able to do that.  Why TLS, well it is all about encrypting your password and data when you connect to your mail server.  In addition, when you use SMTP AUTH, you can travel and your mail server will allow you to send email because you have authenticated. Create ...

Virtual Accounts with CRAM-MD5 The major disadvantage of PLAIN text passwords on the server of course is that they are readable.  Even if your communication with the server is encrypted it is troubling to have readable passwords on the server.  You can easily change this by using the dovecotpw command and creating encrypted ...

SMTP authentication is important because you may use it to verify mail clients independent of their IP Addresses.  Without SMTP Authentication only those IP ranges indicated in the mynetworks parameter will be allowed to connect. So here is how it works with mynetworks. If you had a setting in the Postfix main.cf that looked like the one below, the Postfix mail server at localhost could relay mail and all those machines on the subnet that is listed ...

The environmental variables in CCARGS for instance, provide the options that Postfix needs. AUXLIBS – If you build support for any additional applications you may need to tell the linker where to look for the additional libraries for those programs.  The standard location for system libraries is /usr/lib.  If you want the linker ...

CentOs MySQL Support You may want to use MySQL to store passwords of accounts, especially when you are working with virtual mailboxes.  One thing to note when you do compile Postfix is to make good use of the READMEs are they are very helpful. Be sure that the paths are correct for your distro.  Here you can see the changes necessary ...