14.3 Virtualization

Integration of shared storage into mainstream networking enables ubiquitous access to storage but does not guarantee that such access will be used. Convenient access has little value if storage configuration and management are still manually intensive and complex. As discussed in Chapter 11, storage virtualization promises to simplify administration of storage resources by automating configuration and policy enforcement. At the same time, virtualization solutions must be sufficiently robust to deal with changes or failures in the storage network, one of the main shortcomings of available virtualization products. If a utility pole is under maintenance, customers should not have to phone the power company individually to have service rerouted through the grid or specify how many lamps or TVs they need enabled.

In the ideal storage utility, computing platforms and storage resources are simply connected to the network, and applications are run. Users do not care and do not need to know where, specifically, those resources reside or what magic is being done on their behalf behind the scenes. Virtualization intelligence should be undetectable but highly effective, application-aware, and simple to configure and deploy. Whether they are hosted on servers, SAN switches, or storage arrays, virtualization engines should also be interoperable and capable of supporting distributed configurations across multivendor environments.

Given the complexity of automating storage allocation, quality of service, security, policy enforcement, and resiliency into a virtualization intelligence, it will take considerable engineering to produce viable products even on a proprietary basis. Standardizing that capability presents further complexity and delay but is a prerequisite for widespread adoption. How quickly the ideal storage utility is delivered to users depends on how forcefully customers demand both functionality and standards compliance and how readily vendors respond to the opportunity presented by a mass, utility-driven market.