A key rule in solving any problem, no matter how challenging, is "know your tools!" As you have learned from several of the previous chapters, one such tool is the Spread Group Communication Toolkit. Spread may very well be the Swiss army knife of the distributed systems world, but there are several aspects to consider when choosing to use such a tool. First, you need to properly understand the principles behind the features that the tool provides to pick the appropriate ones to solve a problem. Second, you must evaluate the price that you pay for having features that you don't really needyou don't want to be the hero of the classic tale of squashing a mosquito by using a cannon. Finally, you need to learn how to properly use the tool, to understand its quirks and caveats.
This appendix covers these aspects for Spread, providing a minimal theoretical background, installation instructions, and configuration and usage examples.