Tape and Disk Storage: What do They Really Cost?

As discussed in the latest BlogBytes post, managing overall storage costs is a high priority for data storage managers in 2017. This BlogBytes post will review total cost of ownership (TCO) variables and how they relate to the holistic goals for an organization.

Cost is Not Alone

Those in IT management positions at any organization are not only making decisions to manage cost concerns about data storage, but are also addressing storage initiatives like performance, data access, data sharing, security, protection and compliance. Addressing these matters typically incorporates a strategic blend of storage technologies.  Each of these storage initiatives can affect the overall cost of managing storage and since cost control is a key objective for 2017, let’s do a more holistic examination of storage cost variables.

Go Deep to Discover the Costs

Cost comparisons have been made between tape media and hard disk drives.  Some have argued that tape storage is twice the cost per gigabyte (GB) of SATA HDD storage*comparing the raw media costs of a tape cartridge to an HDD. However, the LTO Program has found that at less than one cent per GB, LTO-7 tape is significantly less expensive than a SATA HDD [1]. Additionally, there have been comments that making a duplicate copy of data on tape can be costly.  Although there is a cost when making copies of data on any storage medium, this cost provides the means to address data sharing, Disaster Recovery (DR) and compliance policies. If these policies are not addressed, it could result in much higher costs or other penalties in the event of a data destructive event. The low cost of a tape cartridge makes it an attractive option to duplicate critical data that can easily be moved to a safe, remote location and address DR best practices. Creating a redundant remote disk system would be a more costly undertaking. It’s fair to say that simple cost comparisons only scratch the surface of the costs and goals associated with an enterprise storage implementation. Let’s look deeper to discover the real costs related to a Total Cost of Ownership (TCO) assessment.

Storage TCO Examined

TCO managed by storage executives contains acquisition costs as well as other supportive and on-going costs including: software, infrastructure/energy, maintenance, personnel, migration and data access costs. These variables were included in a ten year TCO study conducted by the Enterprise Strategy Group (ESG) [2]. The detailed economic analysis was designed to help IT organizations compare the fully burdened costs of leveraging modern storage alternatives for long-term data retention. The study compared an LTO tape-based approach with a present mode of operation (PMO) that represents an all-disk storage approach in-house and in the cloud. As described in the report, the LTO tape-based approach showed “an impressive 577% return on investment over ten years when accounting both for avoided costs and net new economic improvements.” The costs for each of the storage variables for each storage alternative are shown in the ESG chart below, with each variable thoroughly explained in the ESG TCO study. As you can see, when considering all variables that go into an enterprise storage implementation, LTO technology can provide the most cost-effective option.

How reliable is LTO-7 tape?

The ESG report also drew conclusions about the reliability and usage of LTO technology, “Contrary to misconceptions that tape is an unreliable, slow, and antiquated storage technology ESG is pleased to report that LTO tape is thriving and has a bright future in organizations of all sizes, including some of the largest public cloud providers on the planet.

An ESG Lab audit  of LTO consortium reliability testing has confirmed that LTO- 7 media and drives are orders of magnitude more reliable than enterprise-class disk drives. As a matter of fact, it’s more than a billion times more likely that you will get hit by lightning in your lifetime than you will encounter an unrecoverable LTO-7 media error.” [2]

Managing storage and especially analyzing and controlling costs requires a holistic approach that includes all variables that affect the storage organization and total cost equation. As noted in the ESG TCO study, “LTO-based solutions yield a compelling outcome for organizations struggling to cope with fast-growing data, reliable retention, and budgetary pressures.”

*SATA HDD = Serial Advanced Technology Attachment Hard Disk Drive which is a type of computer hard drive standard typically replacing older IDE hard drives
[1] One cent per GB based on LTO-7 tape (compressed) average internet retail price (USD) February 4 2017
[2] Buffington, J. “Analyzing the Economic Value of LTO Tape for Long-term Data Retention”. ESG Report February 2016