Take a journey around the world of Ubuntu 7.10 without exiting from Debian. Along the way, you'll learn how to run multiple Linux-in-Linux instances for development and study.
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All along I have resisted the lure of other Linux distributions and I believe I did not miss much during these years. However, as Ubuntu increasingly became a worldwide phenomenon, I eventually decided to try it but didn't want to leave Debian behind. So I decided to use virtualization: I would run Linux (Ubuntu) on Linux (Debian).