Private Clouds and virtualization have a role to play in the technology revolution that is sweeping across the globe. The impact is felt in the arena of application development, infrastructure requirement or planning for the future trends in technology use.
Virtualization impacts application development for the private Cloud in myriad ways. The design of the application, its development, deployment, and sustenance — in short, its life cycle — is impacted by the concept of virtualization.
Virtualizations help organizations group software resources and abstract it from dependencies of physical implementations to appear like multiple logical resources or a single resource (where multiple resources are harnessed). As a result, virtual servers and virtual desktops can be moved between machines without having to stop application delivery. The virtual machines continue to exist and operate even when hardware is changed / upgraded.
Component wiring is transformed when virtualization and Private Cloud models are adopted. The components can be wired together in distributed or monolithic configurations. If the distributed model is adopted, the components will be distributed across several physical tiers. The physical systems, can thereafter, be converted into virtual systems and replicated in multiple servers to scale up on demand.
In monolithic deployments, the physical system can be converted into a single virtual instance and hosted on a shared physical system. In either case, there will be varying degrees of power savings. Certain Cloud architectures permit the scale up of monolithic virtual applications efficiently. For instance, a web based three tier application can be scaled up by adding additional virtual machines during demand and switching them off when demand falls. Of course, the provisioning for the necessary infrastructure is a given. Cloud services with large resources at their disposal can add or remove the required resources from a specified customer account in tune with the demand cycles.
Concurrent use of virtual applications with physical applications in a private Cloud will determine the amount of resources that may be used up at any given point in time. The virtualization of an application does not preclude the data center from hosting a physical version of the application in the private Cloud. Both versions of the application can be deployed simultaneously, but there will be variations in resource consumption and usage patterns.
There is a maximum and minimum resource usage limit that must be taken into consideration while designing the virtual application and its physical version. The limits can be ascertained by collecting sample data sets and studying use, downtime, peak loads resource use and other related factors. Scale up of the physical version will not be instantly possible. Some products permit conversion of a physical application resource into a virtual application resource.