Managing Large Networks of Virtual Machines

As the number of available virtualization tools and their popularity continues to grow, the way in which virtual machines can be managed in a data center is becoming more and more important. A few commercial tools such as VMware ESX and XenEnterprise exist, but they are limited to a certain virtual machine technology and offer no way to expand the tool's capabilities to local needs. This paper discusses an open source management tool, MLN, for large virtual networks transparent of their virtualization platform. The current version supports the two popular open source virtual machine packages: Xen and User Mode Linux. MLN uses an extensible configuration language for the design of the virtual machines and their internal configuration. Large groups of virtual machines can be managed as logical groups. We present a web-server hosting scenario and a on-demand render farm as case studies to show the usefulness of our tool. The text concludes with a short discussion on the difficulties of offering abstraction to virtualization platforms.