A few years ago, Erik Dahl was a network manager who knew that administrators needed a flexible network monitoring solution. In 2002, he began development of what would become Zenoss, an open source network monitoring product that runs on multiple platforms. Dahl found that the best way to deliver a product that is affordable and customizable is to use open source, and in the process he also discovered that using open source internally is the best way to build a successful business from scratch.