Aggressively Priced Clouds

One of the key reasons for moving to a cloud-based infrastructure is to lower overall infrastructure costs. This is true whether you are building an in-house—private—cloud or are a public cloud provider looking to price your offerings competitively. Because storage comprises such a large part of the outlay of any cloud-based infrastructure, it is an obvious place to look for optimizations that can lower overall costs.

• By Eric Burgener
• Dec 01, 2011

A lower-cost virtual infrastructure gives cloud providers pricing leeway that can be used either to beat a competitor’s price or to increase margins. New storage technologies introduced within the last five years provide significant opportunities to lower storage costs while still creating the type of high performance, scalable and highly available infrastructures that cloud providers need to meet their customers’ business requirements.

Candidate Storage Technologies

The critical technologies in building a cost-effective storage infrastructure include the following:

Scalable, resilient networked storage subsystems. Ensure that the storage you choose is modularly expandable and will scale to meet your business requirements. Networked storage architectures offer better opportunities not only for expansion, but also for redundancy and for storage sharing, which is critical to support the live migration of virtual machines (VMs) necessary to meet uptime requirements. Storage layouts should use RAID for redundancy and provide multiple paths to each storage device for high availability, as well as supporting online expansion and maintenance.

Thin provisioning. Historically, storage has been significantly over-provisioned to accommodate growth. Allocated but unused storage is an expensive waste of space, and thin provisioning is a storage technology that effectively addresses this. By transparently allocating storage on demand as environments grow, administrators no longer have to over-provision.

When thin provisioning technology is initially deployed in an environment, it’s not uncommon for it to decrease storage capacity consumption by 70 percent or more. It allows higher use of existing storage assets, reducing not only hardware infrastructure costs but also energy and floor space costs.

Scalable snapshot technologies. Snapshots have all sorts of uses—working from VM templates, ensuring a safety net during software updates, creating copies for test/dev environments or cloning desktops in VDI environments—all of which have significant operational value. If you’ve worked with snapshots in the past, you probably already know that snapshots can impose negative performance impacts.

In fact, this performance impact can be so bad that administrators consciously limit their use of snapshots in some situations. In others, the value snapshots can provide has helped drive the purchase of high-end, expensive storage arrays that overcome snapshot performance issues. In virtual computing environments, hypervisor-based snapshots generally impose these same types of performance penalties.

Snapshots also can be very valuable when used for disk-based backup. Your customers will expect you to protect their data and provide fast recovery with minimal data loss. To provide the best service to your customers, data protection operations should be as transparent as possible. The best way to meet these requirements will be to use snapshot backups, working with well-defined APIs such as Windows Volume Shadowcopy Services (VSS) to ensure that you can create application-consistent backups for fast, reliable recovery.

For cloud computing environments, the ability to use highperformance, scalable snapshot technology has real operational value. Each cloud provider will need to evaluate how best to meet this need while still staying within budgetary constraints.

Primary storage optimization. SCO technology is not limited to use with secondary storage, and a number of large storage vendors offer what is called “primary storage optimization” in their product portfolios today. Similar in concept to deduplication (but not in implementation), these products effectively reduce the amount of primary storage capacity required to store a given amount of information. Because of their high performance requirements, primary data stores posed an additional challenge that did not exist for secondary storage: whatever optimization work is done must not impact production performance.

Describing the different approaches for achieving primary storage optimization is beyond the scope of this article, but suffice it to say that they can generally reduce the amount of primary storage required for many environments by 70 percent or more, reducing not only primary storage costs but also secondary storage costs (since less primary storage is being backed up).

For Cloud Providers, Cost is Critical

When selling cloud-based services, the set of performance, scalability, and availability requirements are relatively clear, and building the storage infrastructure to meet those needs will likely comprise at least 40 percent of the overall cost of your virtual infrastructure. But there is a big difference in how each cloud provider chooses to get there, and how each leverages available storage technologies to meet those requirements.

The functionality of cloud service offerings for specific markets may be the same across providers that address those markets, but the one who meets those requirements with the most cost-effective virtual infrastructure has a significant leg up against the competition. The storage technologies available in today’s market offer the savvy cloud provider the tools to achieve this advantage.

This article originally appeared in the December 2011 issue of Security Today.