Reaping Value from Storage Networks
- Balancing Offensive and Defensive Strategies
- Primary Defensive Strategies
- Primary Offensive Strategies
- Measuring Returns
- Chapter Summary
The competitive business climate demands increasing data storage capabilities ranging from availability and recovery, to capacity management, to vendor aggregation. Multiprotocol storage networks serve all of these requirements in the form of block-based SANs or file-based NAS. As an enabling platform, networked storage naturally assumes a greater role in the cost and control of the overall storage infrastructure. Chapter 4, “Storage System Control Points,” covered the control aspects of the storage fabric, outlining the areas of intelligence for storage services and the importance of balancing the fabric layer with the host and subsystems layer. This chapter covers the cost component of the storage networking layer by looking at the strategic reasons to combine both defensive and offensive measures and the value achieved by doing so across a common networking platform.
The Internet took the world by storm. The mad dash to put anything and everything digital onto a single network, whether for educational, government, commercial, or experimental reasons, led to data storage requirements and capacity not previously anticipated. Today, many commercial elements of the Internet have reworked business models and adjusted storage capacity requirements. Have you noticed all of the storage capacity restrictions on “free” Web site services, such as online photo sharing and Web-email boxes? Have you noticed how many times you are offered a chance to “upgrade” to the monthly fee option with more storage? Managing storage on the Internet, or for that matter, on any networked environment, includes capital and operational costs that hit the bottom line.
In industries where storage availability and protection drive revenue-generating businesses, the networked storage budget grows as a function of the overall operating budget. To harness these costs and drive ongoing returns from the investment, companies must broaden the metrics for measuring returns. This comes through merging defensive strategies like data protection with offensive strategies like platform consolidation.
5.1 Balancing Offensive and Defensive Strategies
The race to digitized information, which requires 100 percent uptime guarantees, coupled with the world political climate, has driven the role of defensive storage strategies in almost every medium to large corporation. Data storage availability and protection have become the hot topics of the last five years, serving to keep applications up and running, and to restore capabilities at hand if needed in the event of a site disaster. From a budgetary process, these requirements often fly through approval processes compared to other requests. Few executives are willing to tolerate the costs associated with downtime for e-commerce-related business or the costs of losing critical business information that cannot be recovered.
Given this preoccupation with data protection, the build-outs in many organizations have focused on these defensive approaches. Networked storage environments, as the very backbone of data availability and protection mechanisms, are often categorized under this umbrella. In many cases, this provides for adequate project justification. But companies that consider only a defensive approach to storage networking cannot reap the full benefits provided by this infrastructure.
Offensive strategies for storage networking fit hand in hand with defensive strategies but also further maximize the value of a networked storage environment. By looking beyond traditional concepts of data protection to entirely new methods for handling storage, offensive strategies help companies “change the game” and uncover opportunities for operational agility and flexibility that directly impact both capital and operational costs. The primary advantage of a dual-pronged approach to SAN deployment is that the underlying principals of the networked storage environment are similar across both strategies. For example, the same SAN plumbing used to facilitate more efficient backup operations also fits effectively within the larger context of corporate networking, particularly with the flexibility of IP SANs.
Offensive and defensive strategies often overlap. Depending on individual corporate planning processes, the lines between offensive and defensive approaches may vary. Even with a potential gray zone between strategies, the model helps IT professionals evaluate options beyond those traditionally considered for SANs. Figure 5-1 outlines some general distinctions between offensive and defensive strategies.
Figure 5-1. Comparing defensive and offensive storage networking strategies.
With defensive strategies, cost savings frequently relate to short-term objectives, typically the greatest pain points in the process. For example, a company unable to complete regular backups due to excessively long backup windows may adopt a SAN to alleviate the problem. In the race to solve such pressing issues, other considerations may be left out of the picture. For example, will the backup solution also help with storage consolidation? Is it replicable at other offices and locations? Does it fit with requirements for offsite storage in addition to simply reducing the backup window? These questions generally fall into medium- and long-term savings categories associated with offensive strategies.
Asset focus also differs between approaches. The defensive approach focuses on maximizing the use of existing assets, such as extending the life of a tape library by sharing it across multiple servers or using storage resource management to help grab additional capacity from inefficiently used RAID devices. The offensive approach looks at both current and future assets, such as what devices are likely to be part of the infrastructure over time, how they will be managed, and what the best options are for building an infrastructure to accommodate them. For example, balancing a combination of current block-accessed SAN devices with new file-accessed NAS devices requires a platform consolidation approach that is best achieved with a common networking infrastructure such as Ethernet and IP.
Platform choice differs between offensive and defensive approaches. Defensive strategies lean towards conventional platforms, taking incremental moves towards SAN deployment. The typical scenario is a company that has several Fibre Channel servers with DAS devices that moves towards a Fibre Channel SAN. While this deployment will provide SAN benefits, such as higher availability and more efficient backup operations, it still leaves gaps for solutions such as remote backups and integration with NAS. An offensive approach would be to move towards an IP storage network. This leapfrog step provides all the benefits of a SAN, but also gives the ability to keep all the Fibre Channel servers and storage devices with a SAN primarily based on IP networking. While IP as a SAN platform may fall in to the “emerging” category in the storage world, IP and Ethernet have longstanding maturity and robustness from decades of use in the networking world.
5.1.1 Risk and Total Cost of Ownership
Along the lines of comparing deployment approaches, another view of offensive and defensive strategies looks at overall storage growth affecting risk and total cost of ownership (TCO). The proliferation of data storage capacity coupled with the corporate requirements to maintain effective storage management increases both risk and TCO. From a risk perspective, the increase in the amount of data translates into exposure to potential loss. For example, companies relying on customer databases to deliver products and services face potential revenue loss if that information is lost or becomes unavailable. The primary concern for that operation is data protection and availability to reduce the amount of risk.
Increases in the total amount of storage also drive up the TCO. TCO typically includes the capital equipment acquisition costs plus the operational costs over a fixed time period. Companies that try to maintain traditional storage architectures, such as DAS, in the face of ballooning capacity requirements quickly find themselves in a never-ending race to add more storage to more servers while watching management and administration costs skyrocket. In this case, storage network deployment facilitates more rapid expansion of new storage capacity without directly impacting individual server or application operation. With the flexibility of a networked infrastructure in place, total costs decline.
Figure 5-2 shows the effects of storage growth on risk and TCO. In both cases, storage networking strategies—offensive and defensive—help corporations mitigate these effects.
Figure 5-2. Storage growth increases risk and total cost of ownership.
The clear distinction between the approaches is used primarily as a thought framework for the chapter. Certainly, there are defensive approaches that reduce TCO and offensive approaches that reduce risk. However, by separating these two driving forces, IT professionals can more effectively position the project justification and return on the investment when considering storage networking deployment.