What you will learn: Many myths have sprouted up about clustered storage because the term is used to describe so many different kinds of vendor offerings. Here we'll dispel some of these myths.
Myth: Clusters are not grids, grids are not clusters.
Reality: The grid police may not agree, but a cluster is a grid and a grid is a cluster. A cluster can be local or remote and can use proprietary or open solutions just like a storage grid. Some vendors will try to mask a cluster by calling it a grid in an attempt to make it sound unique.
Myth: Clustered storage is only for HPC.
Reality: Some vendors only support high-performance computing (HPC) parallel or sequential data access. Others support concurrent and random small I/Os, including metadata lookup from any node in the cluster.
Myth: Clustered storage is only for parallel or sequential access.
Reality: Some solutions also support OLTP, as well as general file serving, while others can handle bulk storage applications cost-effectively.
Myth: Clustered storage is only for large IT environments.
Reality: Clustered storage can simplify things for small sites leveraging modular growth in terms of performance or capacity or ease of management.
Myth: Clustered storage is only for performance applications.
Reality: Clustered storage is effective for NAS consolidation, as well as home directors, and bulk storage, including near-line archiving of structured and unstructured data.
Myth: More ports, processors, nodes, networks and devices guarantee more performance.
Reality: It's not just about the number of components or speeds and feeds. More nodes, ports, memory and disks do not guarantee more performance for applications.; It depends on how those resources are deployed and how the storage management software enables those resources to avoid bottlenecks. For some clustered NAS and storage systems, more nodes are required to compensate for overhead or performance congestion owhen f processing diverse application workload and performance characteristics.
About the author: Greg Schulz is founder and senior analyst with the IT infrastructure analyst and consulting firm StorageIO Group. He is also the author of the definitive book on storage networking, Resilient Storage Networks, published by Elsevier, and is a regular contributor to Storage magazine and other TechTarget venues.
