I need to know what I need to do to harden the OS before I install my firewall. I read a few articles and it is quiet confusing.
First, let me recommend our sister site, SearchSolaris. There is a wealth of information there regarding Solaris, including a good deal on security.
The primary goals of hardening your server should be to first, remove all services that you don't need, then apply avaliable security patches. Sun provides a toolkit to help you do this.
From their page at http://www.sun.com/software/security/jass/:"The Solaris[tm] Security Toolkit, informally known as the JumpStart[tm] Architecture and Security Scripts (JASS) toolkit, provides a flexible and extensible mechanism to minimize, harden, and secure Solaris Operating Environment systems. The primary goal behind the development of this toolkit is to simplify and automate the process of securing Solaris systems."
For more information on this topic, visit these other SearchSecurity resources:
Best Web Links: Unix Security
This was first published in March 2002