NEW ORLEANS—The open-source Xen hypervisor project was once the only major virtualization technology on Linux. Over the years, its prominence and its community faded, but thanks to a spirited set of initiatives, Xen is now back. In a session at the LinuxCon conference here, Lars Kurth, chairman of the Xen Project Advisory Board, detailed his project’s path from the edge of oblivion to once again being a prominent, well-respected and growing open-source technology.