Jun 16 ’08

Mainframe Tape Technologies:  Myths and Realities

by Editor in z/Journal

Mainframe tape technology is alive and thriving in the data center as organizations discover new ways to leverage tape in the context of their overall storage management strategies. This article explores some common myths regarding tape usage and suggests specific ways to improve the effectiveness and Total Cost of Ownership (TCO) of tape storage. According to Fred Moore, president of Horison Information Systems, a Boulder, CO-based information strategies consulting firm, tape usage goes beyond backup and recovery. Tape storage also is being used to address regulatory compliance, archival storage, risk management, and other issues.

Unfortunately, many IT organizations are still laboring under several popular myths concerning tape. By replacing these myths with the corresponding realities and best practices, these organizations can significantly improve their data management  and operational efficiency—which is important as they grapple with a growing volume of information across the enterprise and budgets that don’t necessary grow at the same pace.

Tape Management Myths and Realities

Myth 1: Tapes have a high TCO.  

Reality: Optimization and automation of tape assets can yield significant cost savings, save time and resources, and reduce overall tape TCO. Underutilization of tape, in particular, is the main driver to high TCO.  

Best practice: Virtual tape technology can reduce physical tape media requirements as utilization of physical tape capacity nears 100 percent. By managing fewer physical tapes, IT organizations can reduce floor space requirements, minimize manual tape handling and get maximum value from their investments in tape media and devices. Automation also ensures accuracy, saves time and improves productivity and effectiveness.

Myth 2: Tape capacity isn’t keeping up with demand.  Reality: Tape capacities have continuously increased and will soon exceed 1TB uncompressed.

Best practice: Increasing effective storage utilization rates maximizes the returned value and useful life of tape media investments and can yield significant media cost savings. This can help eliminate or defer hardware purchases, while reducing the floor space needed for hardware. Less hardware results in lower environmental, vaulting and transportation costs.

Myth 3: Tape media and drive reliability are a problem.

Reality: Both tape media and drives have shown consistent improvements in life expectancy and Mean Time Between Failures (MTBF). Tape media life expectancy is now beyond 15 years and drives are rated into several hundred-thousands of hours. Transfer rates also have improved throughput performance. While IT decision-makers can feel safe knowing that media will enjoy a long shelf life, the retention of older technology is only financially prudent to a point. IT organizations ultimately must decide whether to keep older devices or implement potentially large migration projects to replace both media and devices.

Best practice: Tape vendors routinely introduce technological advancements to their products. IT decision-makers must plan and document near- and long-term tape storage strategies to accommodate potential migrations to new technologies, responses to business issues such as mergers and acquisitions and redesigns of storage environments—such as site consolidation or reduction of physical tape libraries. Automated tape copy utilities will play a key role in hardware and software conversions, media consolidations and electronic vaulting. They also can be used to migrate physical tapes into a virtual tape system.

Myth 4: Tape storage makes it simple to integrate and manage technology from multiple vendors.

Reality: z/OS users can select IBM or Sun StorageTek for mainframe tape drives, media and tape libraries. Integration challenges in a heterogeneous infrastructure include different recording formats, no tape interchangeability, and manual tape management using niche tools or utilities.

Best practice: Media-neutral and vendor-neutral tape resource management tools will reduce complexity by optimizing heterogeneous tape storage infrastructures without requiring extensive training or knowledge. This can help IT organizations avoid being locked into a specific vendor’s proprietary hardware tape system.

Myth 5: The best strategy is to eliminate tape and put everything on disk storage (DASD). Reality: Although some vendors are promoting tape replacement, tape is still the best solution for offsite storage in terms of efficiency, performance, and recoverability.

Best practice: Tape remains the de facto technology to protect and archive data. Tape backup is a key part of the data lifecycle, protecting data on disk and later archived for disaster recovery and record-keeping policies. Generally, IT organizations should store and encrypt long-term or historical data on tape. Tape also should be used to capture periodic “snapshots” of all mission- critical data.

Myth 6: It’ll be easier to access and read historical data years from now if it’s kept on disk.

Reality: Merely replacing one type of media with another doesn’t ensure future recoverability. The ability to electronically store data in a way that will ensure its readability decades later has more to do with being able to document and use record and tape media formats.

Best practice: IT organizations should establish committees that will identify and define specific policies and practices. When creating historical data files, for example, retention policies should mandate that copies of the record formats, existing source code and libraries be included with each type of file. This can be done by simply creating a “read me” Partitioned Data Set (PDS) member or file that contains this vital information. Another relatively simple technique is to “group” the historical data by type or application during tape file creation, stacking and encryption. Some virtual tape solutions today provide the granularity required for grouping of like data. Virtual tape also can simplify the migration from old to new media formats using recycle processes that automatically copy from one media type to the next.

Myth 7: It’s difficult to exploit new technologies using tape storage.

Reality: Tape virtualization and encryption processing workloads are well-positioned to take advantage of IBM’s System z9 Integrated Information Processor (zIIP) and offload those tasks from a mainframe’s general-purpose processors.

Best practice: The extension of zIIP-eligible workloads enables IT organizations to fully protect growing volumes of business-critical data by using the zIIP processor to reduce Million Service Units (MSU) requirements and tape storage management costs. managing keys—especially as more devices that require key management are acquired over time. Other encryption key management challenges include: • The potential need to remount every tape created during the entire year to change keys or address expired ones • Administering responsibilities for controlling and updating keys in a multi-vendor tape encryption and distributed environments—as well as ensuring appropriate tracking and backup • Ensuring encryption keys used to protect historical data haven’t expired if the time comes to read the data • Keeping track of keys in the event of a change in hardware vendors.

Myth 8: Tape encryption provides no business value.

Reality: The business value provided by encryption can be measured in terms of protection from the negative publicity, loss of customers, fines and other consequences of a data breach. According to a 2006 study by the Ponemon Institute, the remediation of compromised data cost businesses an average of $182 per record—totaling as high as $22 million, $4.7 million on average, and no less than $226,000. Costs include legal fees, investigative and administrative expenses, stock performance, customer defections, opportunity loss, public relations, and customer support costs.

Best practice: Implementing a data encryption policy protects the business against the potential serious consequences of a data breach.

Myth 9: Encryption key management provides no business value.

Reality: The business value of encryption key management can be measured in terms of protection from application outages that result from the inability to access encrypted data due to lost or corrupted encryption keys. While businesses can likely tolerate four to five hours of downtime before experiencing significant revenue loss, each hour of downtime can cost up to $25,000 or more when all costs associated with lost sales, wages, and production are considered.

Best practice: By implementing an automated encryption key policy, IT organizations can reduce the risk of application outages and data inaccessibility due to missing or corrupted encryption keys by ensuring protection and availability of keys and digital certificates— and most important, fast recovery of encrypted data.

Myth 10: Encryption keys are easy to manage.

Reality: Encryption key management using manual methods can be difficult. A simple keystroke error can be disastrous—as can a skipped or improperly followed procedure. Such mistakes can lead to the inability to access mission- critical data and keep essential applications down for hours or days. So, while the management of encryption keys may not be a huge burden in terms of hours or difficulty, it’s essential that it be done systematically and consistently. IT organizations also can consider the long-term implication of manually managing keys—especially as more devices that require key management are acquired over time. Other encryption key management challenges include:

• The potential need to remount every tape created during the entire year to change keys or address expired ones

• Administering responsibilities for controlling and updating keys in a multi-vendor tape encryption and distributed environments—as well as ensuring appropriate tracking and backup

• Ensuring encryption keys used to protect historical data haven’t expired if the time comes to read the data

• Keeping track of keys in the event of a change in hardware vendors.

Best practice: IT organizations should implement an automated key management system that consolidates and centralizes key management— including all change, tracking, backup, and recovery processes—across multiple vendors and z/OS tape encryption hardware. They also should consider implementing emerging software technologies that provide automated pregeneration of encryption keys. A good key management system also will protect against the early expiration of keys.

Myth 11: Simple encryption of tape data fulfills compliance with security and risk regulations.

Reality: Encrypting tape data doesn’t guarantee compliance. Data breaches also could involve historical data on older media. This could include data exposed during a move, or compromised by a rogue employee. A common misconception is to consider an environment “compliant and optimized” on the first day of a project involving the implementation or upgrade to new tape technologies or compliance methodologies such as encryption. While such a tape environment may be secure and compliant moving forward, it’s certainly not fully compliant. Corporate managers also need to look backward and include historical data into any total compliance tape strategy.

Best practice: IT organizations should classify and group like data, copying and encrypting historical tape data that contain sensitive information. Software utilities that enable the copying and stacking of data—which keeps “metadata” information intact—are particularly useful for this purpose. 

A variety of scenarios should be considered in creating a total compliance tape strategy, including:

• Any recall of historical data such as for quarterly or annual processing

• Transfer of tape media from one site to another

• Underutilized tapes occupying expensive slots in a silo.


Tape will continue to play a key role in the data center. In fact, z/OS tape technologists can continue to reduce tape storage costs even in the face of expensive devices by more efficiently using tape media.

IT organizations also can take a variety of steps to prevent interruption of business operations. Fast access to data contained on tapes is critical. So is the standardization of tape management tools. Plus, ever-changing IT environments make it essential to implement tools that are flexible and can be scaled to an organization’s specific needs. Data loss is unacceptable.

Efficient utilization and management of new tape technologies and capacities can deliver peace of mind and greater business value. By better managing and automating key tape-related processes, IT organizations can mitigate risk, reduce TCO, fulfill compliance requirements, optimize security, and support “green computing” initiatives.