Storage systems are more than just simple devices where data can be written and then retrieved. They are complex systems with characteristics about the way data is stored and managed and have advanced features that add value when exploited by Information Technology in storage environments. Different storage systems have varying characteristics and features which imply that the value and cost can be quite different. Understanding the requirement for the usage environment is necessary to do a meaningful evaluation for whether a particular storage system meets the needs and the economic value obtained from that system.
In this guide, the characteristics and advanced features commonly available in storage systems are explained to give the reader a broader understanding of storage systems. In addition, the usage environments in a traditional tiering of storage systems with different capabilities are presented. There many different definitions of what tiered usage would be but Evaluator Group is describing the most common as seen in traditional Information Technology environments.
Other Evaluator Group Evaluation Guides give specific detail about particular types of storage systems such as Object, NAS, or SAN. This guide is focused on the general characteristics and use in tiered storage environments.
Characteristics include capabilities such as how the systems connect to servers, physical environments, performance, and resiliency. The advanced features are added capabilities to enable IT to better protect systems and improve operations. These advanced features were once the distinguishing characteristics of systems offered in the high-end enterprise market segment but now are available even in entry level systems. The complexity or completeness of these features can vary and need to be included in the evaluation consideration.
The features include the ability to internally tier data between different performance and cost devices. The devices may be HDDs, SSDs, or caching elements (DRAM, SSDs, or flash cards). Other distinguishing features include support of virtualization hypervisors and integration with external software through APIs.