Appendix A: Pulling It All Together

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You've done it! You've reached the end of this book. If you've actually read (or at least reviewed) the entire thing, then hopefully you know a lot more than you did before about the guts of Linux systems. This appendix wraps things up, makes a few suggestions about what to do with your shiny new knowledge, and tries to play psychic a little bit by discussing future trends.

Running with the Ball: Additional Configurations

The case studies in this book introduced you to three common general system configurations. Where can you go from there? Well, with a little creativity, you can build some really interesting things. Here are a few suggestions:

• Start with the desktop configuration and install the iptables scripts from the firewall configuration. With a little tweaking, you can set up a desktop system that functions as a simple firewall for a network, which may save you from having to have a separate firewall computer.

• Start with the firewall configuration and install a web and e-mail (SMTP) server. (Be security conscious, though!) With a suitable cable modem or DSL connection, this is a great way to run your own Internet domain from your home or office.

• As a more advanced project, build your own virtual private network (VPN) using two Linux systems at different locations. (Chapter 16 discussed this briefly using the Point-to-Point Protocol over SSH; you can start there or use an actual standard IPSec software package.) This can be as simple or as complicated as you need it to be, and you can do anything from simply connecting your home PC to the office network to permanently linking two different sites as a so-called extruded subnet.

With a little experience and creativity, you'll amaze even yourself with the really cool things you can do with Linux-based operating systems. It's a really great feeling when you tame the Linux wilderness and pull off an elegant hack.

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