Taking FC SANs to the Next Level with Clustered/Scalable SANs

Enterprise applications benefit from the non-disruptive operational capabilities of scale-out storage and clustered SAN with the use of Fibre Channel


Today’s enterprises face increasing amount of data that they need to store, manage, and back up. Using scale-out or clustered storage is an advantageous way to respond to growth in a storage environment. Instead of growing a storage system to its limits and then adding another separate storage system, scale-out/clustered storage provides a cluster of storage nodes that operates as a single entity.

All storage controllers have physical limits to their expandability. If more storage or performance capacity is needed, you might be able to add CPUs and memory or install additional disk shelves, but, ultimately, the storage controller will be maximized out. The only option is to acquire another controller and scale up.

In a scale-up configuration, each additional controller is a completely independent management entity that does not provide shared storage resources. If the original controller is to be completely replaced by a newer and larger controller, data migration is required. This is time consuming and likely requires configuration changes on all the attached host systems. If the new controller will coexist with the original controller, there are then two storage controllers to be individually managed and there are no built-in tools to balance or reassign workloads across them.

The situation becomes worse as the number of controllers increases. By using scale-up, the operational burden increases as the environment grows, and the end result is a very unbalanced and difficult-to-manage environment. Technology refresh cycles require substantial planning in advance, lengthy outages, and configuration changes.

To better align IT with the business, use scale-out or cluster storage. This means that, as the storage environment grows, additional controllers are added seamlessly to the resource pool residing on a shared storage infrastructure. Host and client connections as well as datastores can move seamlessly and nondisruptively anywhere in the resource pool, so existing workloads can be easily balanced and new workloads can be easily deployed. Technology refreshes are accomplished while the environment remains online and serving data.

Although scale-out storage products have been available for some time, they typically have focused on engineering applications in a NAS environment. Many vendors also offer clustered SAN or scalable SAN products. Enterprise applications such as Oracle, SAP, Microsoft Exchange, SQL Server, and SharePoint (see Figure 1), will benefit from the nondisruptive operation capabilities and seamless performance and capacity scaling with a clustered or scalable Fibre Channel or FCoE SAN.

Fibre Channel SANs are so prevalent with mission-critical environments that moving to a clustered FC/FCoE SAN environment for a technology refresh, new data center build-out, or greenfield opportunity is a logical move for the following reasons:

Capacity for Scale
• 12PB+ of capacity (example of a 6-node FC SAN)
• 150+ I/O connections (example of a 6-node FC SAN)

Performance for Consolidation
• >250K IOPS (example of a 6-node FC SAN)

Efficiency for Shared Infrastructure
• Support for flash, deduplication, compression, thin provisioning

Designed for Multi-Tenancy
• Logical storage containers for isolation
• NPIV for virtualized fabrics
• FC and FCoE support

• Can perform maintenance and upgrades without system downtime
• Intra- and inter-cluster replication

Be sure to visit FCIA’s Knowledge Vault , a rich resource for IT executives who are interested in learning more on how Fibre Channel can deliver greater business value.

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