Ship in a Bottle - Running Linux Under Linux
David HM Spector
illustrates various ways to emulate Linux under Linux for the purpose
of software development.
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So if you're still in the game, need to test lots of software configurations for your products and services, and aren't allowed to buy or lease any new hardware, what do you do? Clearly, repeatedly building and wiping out a machine or two for software testing is tedious and time-consuming. In this Linux in the Enterprise article, we'll examine some software solutions that will help you "create" enough machines to test against without spending anything more than a little time and some disk space."