Some of the best tools and resources available to system administrators are not commercial products but are available free on the Internet. This appendix contains a list of 30 freely available system administration, networking, and security tools that many top UNIX administrators utilized over the years. If you plan to use any of these tools, it is best to fully test them on a development system and not a production system first.
After the tools list, you'll find a list of fantastic organizations that UNIX administrators should think about being a part of. They can provide a wealth of information in helping you as a computer professional stay current in the industry.