Rethinking Server Virtualization

Introduction
Server virtualization is an ever more important tool for reducing cost, increasing availability, and enhancing business agility. But for many organizations, the savings that come from server consolidation are the primary reason for server virtualization.

Many of virtualization’s additional benefits—including built-in, cost-effective high availability (HA) and disaster recovery (DR)—require external shared storage with a comprehensive feature set to support them. Without proper planning, it is all too easy to see the savings from server virtualization be misdirected toward inefficient storage systems. IP SANs are frequently seen as overcoming cost and management limitations of traditional storage area
networks (SANs) and are becoming very popular in virtualized server environments.

Advantages of scale-out iSCSI SANs
HP StorageWorks P4000 G2 SAN Solutions are iSCSI-based and use storage clustering—a form of scale-out storage that creates a scalable storage pool by aggregating the critical components of a number of storage systems into a single pool of resources or storage cluster (Figure 1). The cluster accepts and responds to iSCSI requests as a single system. In an HP P4000 G2 SAN all physical capacity is aggregated and is available to all volumes created on the SAN.
When more storage is needed, additional P4000 storage nodes can be added to the SAN cluster online; the SAN seamlessly, non-disruptively reorganizes its storage to incorporate the new node into the cluster.

Built-in support for HA and DR implementations, superior, scalable performance, and straightforward management that any server administrator can understand and put into use make HP P4000 SANs the preferred choice to support virtualized infrastructures. This white paper describes the advantages of scale-out iSCSI storage in four areas—cost, high availability and disaster recovery, performance, and management—and illustrate how the HP P4000 SANs provide better overall support for virtualized environments.