User Mode Linux

Chapter 4. A Second UML Instance

Now that we’ve seen a single UML instance in action, we will run two of them and see how they can interact with each other. First, we’ll boot the two instances from a single filesystem, which should cause them to interact with each other by corrupting it, but we’ll use a method that avoids that problem. Then, we’ll continue the networking we started in the previous chapter by having the two instances communicate with each other in a couple of different ways. Finally, we’ll look at some more unusual ways for UMLs to communicate that take advantage of the fact that, as virtual machines, they can do things that physical machines can’t.

COW Files

First, let’s fire up our UML instances with basically the same command ...