Based on current and proposed products, it appears that a grid storage system should include the following:
Modular storage arrays: These systems are connected across a storage network using serial ATA disks. The systems can be block-oriented storage arrays or network-attached storage gateways and servers.
Common virtualization layer: Storage must be organized as a single logical pool of resources available to users.
Data redundancy and availability: Multiple copies of data should exist across nodes in the grid, creating redundant data access and availability in case of a component failure.
Common management: A single level of management across all nodes should cover the areas of data security, mobility and migration, capacity on demand, and provisioning.
Simplified platform/management architecture: Because common management is so important, the tasks involved in administration should be organized in modular fashion, allowing the autodiscovery of new nodes in the grid and automating volume and file management.
Three Basic Benefits
Applying grid topology to a storage network provides several benefits, including the following:
Reliability. A well-designed grid network is extremely resilient. Rather than providing just two paths between any two nodes, the grid offers multiple paths between each storage node. This makes it easy to service and replace components in case of failure, with minimal impact on system availability or downtime.
Performance. The same factors that lead to reliability also can improve performance. Not requiring a centralized switch with many ports eliminates a potential performance bottleneck, and applying load-balancing techniques to the multiple paths available offers consistent performance for the entire network.
Scalability. It’s easy to expand a grid network using inexpensive switches with low port counts to accommodate additional servers for increased performance, bandwidth and capacity. In essence, grid storage is a way to scale out rather than up, using relatively inexpensive storage building blocks.