Features - Enterprise Data Insights:

STORAGE VIRTUALIZATION: NEXT STEP IN CONTROLLING COSTS

By eliminating the complexity of the storage environment, virtualization lets you reduce ownership costs.

Simplify, Simplify, Simplify

Although hardware prices have come down in recent years, storage administration expenses still run about seven times the cost of hardware. For many businesses, controlling these costs is crucial to lowering the total cost of ownership. Storage consolidation provides a partial solution by expanding device connectivity and reducing points of management. However, once storage is consolidated, the job is only half done. You still need a centralized, flexible method of management that masks the complexity of the storage environment and reduces administrative overhead. That's where virtualization fits in.

Focus On The Task -- Not The Technology

Operating system technologies have moved toward virtualization in a variety of areas, but the goal is the same: to make a complicated task easy to perform. Thus, memory management has evolved from having to manually assign a fixed amount of memory for each process to a virtual memory subsystem that dynamically allocates memory as needed. Likewise, e-mail communication was once restricted to individuals who could understand arcane network routing schemes. Today, you simply type the destination address; switches and routers make sure the e-mail reaches the correct server.

As with memory managment and e-mail, storage virtualization seeks to simplify cumbersome tasks-like allocating storage, load balancing, configuring RAID, and backing up and restoring data. Optimally, the physical disks and complex underpinnings of the storage are concealed from administrators and servers. Disk space is presented to the operating system as a "logical volume" that appears to be a normal disk or partition. With a layer of abstraction between storage and hosts, administrators are no longer bound to the physical dimensions of a disk or forced through complex steps to perform basic storage management tasks. Not only does virtualization improve efficiency and productivity, it reduces the time, effort and knowledge needed to manage storage.

Not All Solutions Are Created Equal

If the objective of virtualization is to make the life of a storage administrator easier, not all solutions effectively meet this goal. Early generation virtualization products provide flexibility, but they are essentially consolidated storage solutions that do little to reduce complexity. Some actually increase the number of components to manage, and load balancing, RAID configuration and provisioning remain difficult, manual operations.

To address these inadequacies, next generation virtualization solutions mask the underlying complexity of the storage environment by providing a "pool" of protected storage, not just a set of consolidated disks. Loads can be balanced and logical volumes created and expanded-on demand and with no user impact. RAID configuration and backup, replication, and snapshot capabilities are integrated and transparent to applications.

Comparisons Of Virtualization Methods

• Host-based (volume manager)-- supports multi-vendor storage systems

  Deficiencies:

  • Many points of management
  • Single software vendor
  • Difficult to deploy especially with mixed platforms
  • Must install and manage software on each host
  • Slow snapshot capabilities
  • Storage pool limited to a single host.

• In-band appliance (located in I/O path) -- supports multi-vendor storage systems; optimizes performance dedicated switch

  Deficiencies:

  • Additional point of management
  • Single switch vendor (difficult network upgrades)
  • No knowledge of device capacity or status
  • All I/O must flow through applicance
  • Steals bandwidth from host
  • Slow snapshot capabilities.

• Out-of-band appliance -- supports multi-vendor storage systems; optimizes performance

  Deficiencies:

  • Additional point of management
  • Single switch vendor (difficult network upgrades)
  • No knowledge of device capacity or status
  • May not support all platforms
  • Must install software on host (or HBA)
  • Steals bandwidth from host
  • Slow snapshot capabilities

• Storage subsystem -- Reduces management complexity; standard network hardware; optimizes performance; integrated RAID management; fast snapshot capabilities; can co-exist with other solutions

  Deficiencies:

  • Some products limit storage to a single array
  • Single storage vendor.

Early generation virtualization does little to improve ease-of-use:

• Increases components to manage
• Only consolidates storage
• Tasks remain complex and obtrusive.

Next generation virtualization simplifies storage administration:

• Decreases components to manage
• Provides pool of storage, not just disks
• Masks complexity of tasks
• Operations are transparent to users.

The Future Is Here

As shown in the above table, a storage subsystem-based product that can span arrays represents the ideal virtualization solution -- providing a scalable "pool" of storage, in addition to technology that hides the underlying configuration, regardless of its complexity. EqualLogic Inc is delivering such a product with its PeerStorage Array, which combines the best of storage consolidation and virtualization in an iSCSI-based SAN. By leveraging existing network infrastructure and personnel skills, EqualLogic provides a cost-effective, high-performing, scalable storage solution. Just what businesses need to decrease the cost -- and the complexity -- of managing storage.

For more information on EqualLogic's PeerStorage solution, visit www.equallogic.com or email info@equallogic.com.