Anyone who purchases storage arrays is familiar with the many advantages modular storage systems and storage area networks offer. However, they may also be familiar with one of the less desirable attributes of storage arrays: the typical 3-yr to 5-yr life cycle that forces decommissions and mandates upgrades on a regular basis. With many organizations expanding their need for storage by 20-60% on an annual basis, outgrowing capacity of existing storage arrays is a regular occurrence, effectively rendering upgrade cycles to be a fact of life.
Although decommissioning and upgrading a storage array may not appear all that daunting, the process includes a number of cumbersome aspects:
- First, the migration process from old to new storage arrays could last months, creating an overlap when both the old and a new storage array must be maintained. In some enterprise environments, the migration could even cost thousands of dollars per Terabyte (read “Reducing Costs and Risks for Data Migrations” research paper by Hitachi Data Systems for more on the topic of costs)
- Second, when purchasing a new storage array, its sizing is selected based on anticipated future growth, resulting in an initial capacity “over-purchase” and an underutilized storage array for most of its life cycle. Result? Pre-payment for capacity you may not need over the next 2 years
- Third, software and architectural changes associated with each storage array upgrade may compromise stability or, at a minimum, require staff retraining on new tools, policies and features
So why decommission arrays at all? Why not simply expand storage capacity by adding new storage arrays instead of replacing them? Well, with storage densities and capacities growing every year and cost per GB dropping every year, the economics provide the answer.
Let’s say you own a 10TB storage array from 3 years ago that cost $50K to purchase and has a total annual maintenance cost (vendor maintenance fee, administration, floor space, power, cooling, etc) of $25K per year. Now let’s say today you purchase a new 25TB storage array for $50K. Thanks to improved storage density, you may find it carries the same total annual maintenance cost of $25K per year.
If you choose to keep both arrays active, you would now have data residing on the old storage array at $2.50/GB in annual maintenance cost and data residing on the new storage array at only $1/GB in annual maintenance cost (with plenty of capacity to spare). This economic inefficiency makes a pretty strong business case for decommissioning the old array and moving all data to the new array as quickly as possible.
So is there any hope of breaking this storage array cycle?
There is indeed hope with on-demand cloud storage. Cloud storage substantially changes the economics and deployment of data storage and makes some of the aspects of the storage array life cycle start to disappear entirely.
- With a pay-as you-go model, there is no longer a need to ever pre-purchase or over-purchase capacity
- The yearly cost per GB drops every year as cloud providers continue to lower costs every 6-12 months
- Storage capacity is virtually limitless, so there is never a need to decommission or upgrade any hardware
Sound appealing? Look for part II of this series, where we’ll examine exactly how cloud storage can start to break this storage array life cycle.