In Chapter 2, we found the increasing size of online data to be a driving factor in pushing the limitations of the traditional client/server storage model. The processes that surround the design and development of business applications, and which fuel data growth, are not equipped to supplement the planning and design of storage infrastructures , no matter how critical storage becomes. Once applications reach production stage, the realities regarding actual users and the limitations of current storage environments are quickly quantified in application performance. The addition of support applications, generally addressed as an after thought, will further increase demands on new or current storage devices. As the likelihood of major renovations to existing storage infrastructures increases , post-implementation enhancements become very active, while the impact on business driven by the risk to successful application implementation becomes an even greater concern.
A solution to these problems is the design and implementation of more scalable and responsive storage infrastructures based upon storage networking concepts. As we discussed in Chapter 2, storage networking requires separating the traditional storage components from their server counterparts. This is a major shift from tightly coupled architectures of the traditional client/server era. However, once implemented, users can greatly benefit from increased scalability in both size and access and lower the risk of application implementation and maintenance failures.
This chapter will explore the concepts surrounding one of the current and increasingly popular models of storage networking: Network Attached Storage or NAS. NAS facilitates the decoupling of storage from the server by allowing storage to be directly connected to existing client/server networks. It provides a method of addressing the data access and storage challenges, while creating a scalable storage infrastructure that will support multiple applications. In addition, this model can compensate for the lack of planning that generally arises in the implementation frenzy of application development, not to mention the ad hoc need to provide ongoing storage capacity for business demands.