This tutorial will tell you how to setup a basic mail server and attempts to teach you a bit about the Postfix MTA (Mail Transfer Agent) in the process.
In early 2006, Marshall University laid out a plan to migrate HOBBIT (Figure 1), an HP OpenVMS cluster handling university-wide e-mail services. Plagued with increasing spam attacks, this cluster experienced severe performance degradation. Although our employee e-mail store was moved to Microsoft Exchange in recent years, e-mail routing, mailing list and student e-mail store (including IMAP and POP3 services) were still served by OpenVMS with about 30,000 active users. HOBBIT's e-mail software, PMDF, provided a rather limited feature set while charging a high licensing fee. A major bottleneck was discovered on its external disk storage system: the dated storage technology resulted in a limited disk I/O throughput (40MB/second at maximal) in an e-mail system doing intensive I/O operations.
SQLgrey is a postfix policy service implementing a grey-listing policy.
SQLgrey is written in Perl and uses DBI to access an SQL database.
Its goal is reducing the SPAM reaching user mailboxes
G. Kothari, A. Ahuje, A. Patel, and A. Khilari. International Journal on Recent and Innovation Trends in Computing and Communication, 3 (4):
1802--1806(April 2015)