Crossroads' StrongBox: Securing the Future of Data Archiving

If you were asked which storage product--hard disk drives (HDDs) or tape--would decline precipitously in market share during the next five to 10 years, you would probably be one of the vast majority of people who said tape. You would also be wrong. Winning storage technologies have to excel on at least one dimension (either performance or capacity) and tape excels on capacity.

As a result, as active archiving becomes more important to your enterprise, tape will play a major role to meet the high-capacity requirements that the active archiving IT revolution will demand. A number of IT vendors, both large and small, will play significant roles in that revolution. However, Crossroads and its StrongBox product seem likely to play a crucial part in tape’s upcoming significant position in active archiving.

Before we examine Crossroads’ StrongBox, we need to understand the relative future roles of HDDs, solid state drives (SSDs) and tape. The successor technologies to flash memory (which are already on the drawing boards in storage R&D labs) will dominate the performance segment of the storage market. HDDs simply are not increasing in speed fast enough to overcome the advantages of solid state device technologies. Although HDDs may (or may not) retain a relative price advantage over solid state devices, the absolute cost (that is, the money that enterprises have to shell out) will fail to overcome the value benefits of the solid state devices when high performance (as measured in response time latency requirements) is mandatory.

What about capacity? Well, we have already seen data migrate from high performance disks (say, Fibre Channel disks) to more friendly cost-per-gigabyte drives (such as SATA disks). Why isn’t this sufficient? The answer is that although some might disagree that tape, at sufficient scale, is much more cost efficient than disk, the majority of data is fixed content data (that is, not subject to change), which does not require fast response times, so the most cost-efficient technology wins (especially when the difference in efficiency is significant).

But, wait, some might say. What about manageability? What this boils down to is that disk can use a file system for management and, until recently, tape did not have that advantage. But with the introduction of the linear tape file system (LTFS, a single, non-proprietary media storage standard for tape), that advantage has gone by the boards. Tape can now be managed as if it were disk.

But, wait again, say the critics. Huge tape cartridges still have to store files in a linear fashion, and finding a particular file may take time--say, a minute or more compared with the seconds required by HDDs. Note, however, that the first part of each file can be placed on a "disk" cache, where disk may be either an HDD or SDD device. This may be enough to save precious time.

Moreover, recall that information is typically stored on tape for long-term retention, which means that access is very infrequent and search time may not be much of a factor. If a piece of information becomes hot in the sense that it suddenly becomes active (that is, frequent accesses), such as biographical files about a famous person who just died, then they can be positioned on disk until the hot spell subsides. Also, some data retrieval can be scheduled, such as medical images called up prior to a doctor’s appointment, and other files can be subject to analytical processing (such as big data), where the initial latency is so small as to be irrelevant to the overall length of processing.

Now, despite these scenarios, all is not rosy for the tape market. Disk-to-disk storage technologies will be used more and more for initial backup and restore requirements. However, the use of tape for active archiving will be a growth market for tape. As a result, HDDs will suffer from disintermediation at both ends of the spectrum. SSDs will be used for high-performance applications, and tape will be used for capacity. This does not necessarily mean that HDDs will disappear from the face of the earth. One might be able to construct plausible use cases where HDDs still play a role. But it will be significantly impacted.

Still, enterprises are not concerned about the fate of particular technologies, but rather what their fates entail. Although organizations are starting to grow more comfortable with SSDs, they probably have not thought about what an extensive move to active archiving, especially involving tape, will entail. That’s an issue where Crossroads seems well-positioned to influence and prosper, so let’s examine the role the company’s StrongBox solutions will play in continuing to advance the use of tape in active archiving.

Though active archiving stores fixed content, that data still has to be accessible online, where online means that users can retrieve information without the intervention of an IT professional. Tape was seen at best as being a nearline solution, requiring the services of an IT professional for retrieval, or more likely offline, meaning tape media has to be manually loaded into a tape drive as part of an overall retrieval process. The introduction of LTFS enables tape to be used online, albeit not with the response times needed for such applications as online transaction processing systems.

Crossroads' StrongBox exploitation of LTFS offers an illustration of how to bring active archiving to life on tape. StrongBox is a fully portable data vault manager for long-term retention of data. Key characteristics include its ability to allow online, all-the-time and non-proprietary access to data, including e-mail, database, and file archives.

StrongBox is instantiated as a physical appliance between servers that request I/Os of the active archive as if they were disk I/O requests and tape automation products that fulfill those requests. Each StrongBox contains read and write cache to manage the files. The company’s model T1 is a 1U server that supports up to 200 million files at a maximum file transfer rate of 160 Mbytes per second. The model T3 is a 3U server that supports up to 5 billion files with a maximum file transfer rate of 600 Mbytes per second. Crossroads has been around for quite a while and has a good reputation for delivering enterprise-class quality products, including high availability solutions.

StrongBox presents itself as a NAS device, so it allows simultaneous application, user and file access (a necessity in this environment). It can also participate in standard SAN environments without any application modifications. In fact, a big point to emphasize is that it requires no changes to current practices and procedures. StrongBox enables a vendor-neutral archive that does not require any dependency on operating systems, applications or specialized agents. No changes to applications or file formats, attributes, privileges and rights are required. It monitors and manages all generic LTFS tapes. Note that the fact that tape is being used as a Tier 3 storage layer for an active archive is transparent to the end user, although IT professionals are well aware that StrongBox is helping them manage an environment that includes tape automation.

Crossroads cites user examples of the benefits that StrongBox can achieve. One healthcare technology service provider projected the cost of storing a petabyte of data on HDDs versus using StrongBox. The latter delivered nearly an order of magnitude of savings during a five-year time period.

A couple of side benefits to using tape are that tape uses minimal power and has a long shelf life. A piece of tape media in a tape library, but not currently in a tape drive, uses no power. The alternative concept of MAID (Massive Array of Idle Disks) for disk, where disks are powered down when not in use, has never really taken off. Tape also has a longer shelf life than disk (to the surprise of many), which means that technology refreshes with tape can occur at longer intervals than disk typically requires. All in all, StrongBox appears to deliver an all-the-time-on, easily accessible data vault for the long-term management of data at a more effective price point than can be obtained with disk-only solutions.

Active archiving is actually just one of a number of IT revolutions that are going on today. However, it might best be characterized as the quietest IT revolution, especially because tape (whose death has been proclaimed for decades) will take a leading role. Now, even though this means that tape will have as disruptive an impact on HDDs as do SSDs, SSDs are more glamorous than tape. Other trends--such as big data, cloud computing and the continuing proliferation of mobile devices--will continue to drive the lion’s share of public attention. Yet without using active archiving and tape to provide for the long-term preservation of data in a form that still enables drawing ongoing value from information as needed, enterprises might choke on excessive costs and the other revolutions will not be able to achieve their full potential.

Overall, we consider Crossroads’ StrongBox product to be a key enabler of the quiet revolution. IT professionals should like the fact that they don’t have to change the way they do business (assuming that they already have a tape automation environment) to use a StrongBox. Business users will have access to data that still has business value but might have otherwise been too expensive to keep. Financial professionals, whose eyes are focused on the bottom line, will appreciate the cost efficiencies of a tape-based active archive. With Crossroads’ StrongBox playing a central role, maybe the quiet revolution won’t be so quiet after all.

At the time of this publication, Crossroads is not a current client of David Hill and the Mesabi Group.