Virtual Machine Migration Method between Different Hypervisor Implementations and Its Evaluation

Virtualization technologies are an important building block for cloud services. Each service will run on virtual machines (VMs) deployed over different hyper visors in the future. Therefore, a VM migration method between different hyper visor implementations will be required. Existing methods, such as VM image conversion, generate dead copies of VM images during migration. This causes an operating system running on a VM to fail to boot up after migration and to identify virtual devices provided by destination hyper visors because the dead copied image does not contain requisite files for booting up the copied VM environment. To solve these problems, we propose a VM migration method that generates a destination-dependent VM image before migration. The destination dependency is a set of requisite files enabling a guest OS to boot up from the image, and is determined from the device configurations of destination physical machines and virtual ones. The proposed method extracts the dependency from the file structure that enables the guest OS to run on the destination hyper visor. Our evaluation confirms that the proposed method succeeds in VM migration between hyper visors such as VMWare, Virtual Box, and VirtualPC. As for performance efficiency, our method can reduce the size of a transferred VM image to approximately 20% that of a source VM image.