Sendmail and Qpopper with SSL/TLS support
Linux Security Guide
Iptables Tutorial
Advanced Bash-Scripting Guide
Cyrus howto
Good Milter plugins
Apache setup
Apache SSL certificate update
Create SSL cert V2
IP routing
Maximum security
Anti SPAM tools / database
How to replace exchange
Tim's Sendmail REGEX Patches
Guide to IP Layer Network Administration with Linux
Guide to Bind 9.2.X
Perl modules update/ upgrade / check
Iptables tutorial 1.2.0
Time set
UTP cable connection wiring


A good book on Security : Real World Linux Security ISBN 0-13-028187-5

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