Slamming Spam : A Guide for System Administrators

Offers sys admins vital help in managing spam and keeping its load off their networks.

Dale Nielsen is a partner in Avacoda LLC, a consulting company specializing in systems administration and software development.

Slamming Spam: A Guide for System Administrators PrefaceThis book is meant to be a reference for the email system administrator who has been asked to implement an anti-spam solution for their organization. This is an administrator's "how to" stop spam book. It is very hands on, with none of the "why people spam" or other topics which are usually only peripherally interesting or useful to a mail administrator.Fighting spam is a complex problem, with many potential technical, legislative, and social solutions. No book could ever hope to cover them all in a reasonable amount of space. In fact, when considering only the possible technical spam-fighting solutions, it isn't possible to give them all the coverage they require. Our focus in this book is on the widely used open source anti-spam solutions available for major mail transfer agents (email servers).Be sure to check out the web site for this book at http://www.slammingspam.com . It has all the latest information on the book, including updated URLs, errata, and other useful information in the fight against spam. Who This Book Is ForThe reader is assumed to have a limited knowledge of Linux/Unix. In most cases, step-by-step instructions are provided for the covered package or approach. These "cookbook" examples are meant to work for most installations, with minimal changes and/or customizations. While some knowledge is assumed of the mail-transfer agent software used (such as Sendmail), the administrator doesn't need to be a mail server expert or Linux guru to implement the solutions outlined here.You will learn about the best current anti-spam methods and software available. Most of the methods are open source and freely available (as in free beer). These open source solutions offer the "best of breed" anti-spam solutions available today. Implementing open source solutions requires more work than commercial solutions, but often the administrator ends up with a more flexible, better solution than is otherwise available.We initially thought we would discuss anti-spam services such as Postini and Symantec's Brightmail in the book. However, we found that most of the commercial anti-spam solutions (such as anti-spam firewalls) and services were documented quite well and didn't require additional coverage. As a result, most commercial solutions are only mentioned in the Introduction. The only non-open source anti-spam solution covered here (McAfee SpamKiller) is directly related to the commercial mail servers covered--IBM/Lotus Notes/Domino and Microsoft Exchange.The IBM Lotus Domino and Microsoft Exchange administrator has a choice. An anti-spam solution can be implemented directly as part of the mail server, since both IBM Lotus and Microsoft Exchange support plug-ins. To supplement or as an alternative to a tightly integrated solution (like McAfee SpamKiller), additional open source email servers can be deployed specifically to perform spam filtering or virus checking. These anti-spam/virus servers would process the message before sending it on to the Domino/Exchange server for delivery to the recipient.While adding to the "box count" an administrator needs to manage, this approach does enable an open source best-of-breed solution to these otherwise "closed" commercial email servers. A hybrid approach can reduce the out-of-pocket cost while giving the administrator much flexibility in tweaking the anti-spam solution. What You Will NeedThe solutions in this book focus on Linux, on the server side. There is some coverage of the client side, but primarily the client coverage is meant to complement the server implementations we examine. Although the solutions