1. A method of distributed software application virtualization in a network of computer device systems, comprising: configuring at least two systems in the network for distributed application virtualization by providing each of the two systems with a distributed software virtualization service; generating a virtual distributed application layer that spans the two systems in the network; adding a distributed software application to the virtual distributed application layer; providing mapping data that comprises information that identifies a destination file path in the virtual distributed application layer to which access requests are to be redirected; activating the virtual distributed application layer in one of the two systems in the network and notifying the other of the two systems, via the distributed software virtualization service resident in the one of the two systems, of the activating of the virtual distributed application layer; intercepting, at a filter driver of a virtualization engine, a first access request from one of the two systems for a file from an original file path in a base file system; using, based on the virtual distributed application layer being activated, the mapping data to redirect the first access request from the original file path in the base file system to the destination file path in the virtual distributed application layer; deactivating the activated virtual distributed application layer in the one of the two systems in the network and notifying the other of the two systems, via the distributed software virtualization service resident in the one of the two systems, of the deactivating of the virtual distributed application layer; intercepting, at the filter driver, a second access request from one of the two systems for a file from the original file path in the base file system; allowing, based on the virtual distributed application layer being deactivated, the second access request to pass through to the original file path in the base file system instead of being fulfilled from the destination file path in the virtual distributed application layer.