Abstract: Migration of a virtual machine from a source host computing system to a target host computing system in a context in which a centralized portion of virtual machine state is maintained in a storage that is accessible to both the source host computing system and the target host computing system, and a localized portion of the virtual machine state is maintained in local storage of the source host computing system. For instance, the centralized portion of the virtual machine state might be user data, and the localized portion might be backing files for the virtual machine. In order to support the potential migration, at least a portion of the localized portion of the virtual machine state are backed up to a storage that is accessible to both the source and target host computing systems.

Abstract: The migration of virtual machines internal to a cloud computing environment. The cloud maintains the replicas for virtual machines that could be migrated. The cloud also is aware of location of user data for each of the virtual machines. The replica together with the user data, represents the virtual machine state. If migration to the cloud computing environment is to occur for any given virtual machine, the cloud computing environment correlates the replica with the user data for that virtual machine, and then uses the correlation to instantiate the virtual machine in the cloud.

Abstract: A communication model in which application(s) above a hypervisor use a file system having one data access model (e.g., a block-based file system) to access an underlying storage device having another data access model (e.g., an object-based file system). This is accomplished via an intermediary component that converts input/output requests and responses from the file system data access model into the underlying storage device data access model, and vice versa. As an example, virtual machines operating a block-based file system using a hypervisor may interface through the intermediary component with an object-based storage device. Thus, the prolific use and availability of block-based file systems may be used compatibly with highly efficient object-based storage devices.

Abstract: Allocation of software and data support resources for a virtual machine between a physical support environment and an external location, and migration of a virtual machine between physical support environments. Prior to migration, the virtual machine operates on the first physical support environment using a resident portion of the support resources that is resident on the first physical support environment, and an external portion of the support resources that is not resident on the first physical support environment. The virtual machine is then migrated to a second physical support environment that either already has access to or at least has the capability of accessing a copy of the resident support resources. This migration may be accomplished by mapping a copy of the resident support resources on the second physical support environment to a copy of the external support resources. This allows migration without contemporaneously copying the external portion.