Postfix

Postfix is a popular [[Mail Transport Agent (MTA)]] used for routing and delivering email on the Internet. It is an open-source software application that serves as an alternative to [[Sendmail]], the traditional MTA for Unix-based systems.

Postfix was designed with a strong emphasis on security, aiming to mitigate the vulnerabilities that were prevalent in other mail servers like Sendmail at the time. It uses a modular architecture where different components run with minimal privileges to reduce the impact of potential security breaches.

Known for its performance, Postfix can handle a large volume of email efficiently, making it suitable for both small and large email systems. Compared to Sendmail, Postfix is easier to configure, with a simpler syntax in its configuration files. This accessibility makes it a preferred choice for system administrators.

It is highly flexible and can be integrated with various databases, mail processing programs, and spam filtering solutions. Postfix is designed to be compatible with existing Sendmail configurations, allowing for easier migration from Sendmail to Postfix.

It is primarily used as an [[Simple Mail Transfer Protocol|SMTP]] server in a variety of environments, from small-scale to large-scale email systems. Postfix routes and delivers email, handling tasks like queue management, policy implementation, and client requests.

Postfix can be installed from the package repositories of most Unix-like operating systems. The configuration files are typically found in /etc/postfix. The main configuration file, main.cf, is well-documented and allows administrators to control various aspects of the MTA's operation.