Unix System Security Tools
- An introduction to Unix security tools, including Ten General Security Rules.
- http://www.albion.com/security/usst/

BlogFish
- Weblog by Jonathan Weiss about Unix, BSD, security, Programming in Ruby, Ruby on Rails and Agile Development.
- http://blog.innerewut.de

Unix and Security Services and Solutions
- Providing administration, installation, integration and consulting services for Unix and Security products and solutions.
- http://www.proxysystems.com

Computer Security
- How to secure your Unix computer system (emphasis on HP-UX).
- http://www.unixtools.com/security.html

Secure your Digital UNIX (Tru64) Alpha
- Notes for securing a DEC/Compaq Alpha running Tru64 UNIX.
- http://www.maths.usyd.edu.au:8000/u/psz/securedu.html

SysAdmin & Security Resource Center
- Security, networking and UNIX resources for system administrators.
- http://www.syslog.org

OpenBSD release errata
- the OpenBSD CD errata page
- http://www.openbsd.org/errata.html