While tape's limitations as a storage medium have been widely documented over the years, it remains the cheapest way to store large amounts of information today. And there's no shortage of it out there.
One linear tape open (LTO)
LTFS, or Linear Tape File System, allows data on version 5 and subsequent LTO tapes to appear in a hierarchical format and be searched as if it were on disk. To date, most LTFS adoption has been among organizations dealing with large amounts video archival.
For example, Crossroads Systems announced in January that the San Diego County Communications Office deployed their Strongbox device to protect 25 TB of the county's video assets. The Strongbox device sits in front of a tape library and uses LTFS for what many have called "Tape NAS" -- allowing data on the library to be searched and accessed as if were on disk. Tape library and backup software vendors, however, have been slow to integrate LTFS, but we're beginning to see some increased activity.
"Some vendors are placing the LTFS management command, control and data movement functionality into their libraries; others into their software-defined appliances; others as software modules you can download for free or fee; others are even making their file systems proprietary or open source," said Greg Schulz of Storage and ServerIO.
The latest developments in this space, along with the push to store vast amounts of data for analytics, may push LTFS into use for enterprise data archiving, but it's still unclear if LTFS will move beyond its current niche.
New LTFS-enabled products
In the past year, a number of leading tape system vendors took steps to integrate LTFS across entire libraries.
In October, Spectra Logic Corp. announced the BlackPearl Deep Storage Appliance -- a tape-based object storage system that includes a RESTful interface. RESTful object-based storage is catching on as a way to manage large numbers of files internally or in the cloud. The company's Deep Simple Storage Service allows tape libraries to access the RESTful architecture. The company said it opted for an object storage interface to optimize data management. Rather than being used as a file system, the company said LTFS integration will ease data migration to future iterations of LTO tape -- an important consideration for long-term archiving of data because it could alleviate the need to maintain older technology to access data.
In September, Oracle announced their Oracle StorageTek SL8500 and SL3000 libraries would support LTFS using StorageTek Linear Tape File System, Library Edition (LTFS LE) and T10000 drives. LTFS LE allows users to search, index, and drag and drop files in the libraries. Oracle previously supported LTFS on drives running on single cartridges, but this is its first library-wide LTFS support.
"Spectra's BlackPearl extends LTFS and tape libraries to full object-addressable storage. It enables search and discovery. It adds context and meaning to 0's and 1's on linear tape, beyond just a file name. The object capabilities help to enable functions such as keeping rich media files updated with the latest formats," said Ben Woo of Neuralytix. "Oracle's approach is by adding objects in a higher layer. Both solutions have benefits depending on the legacy aspects and the preferred philosophical approach of a particular enterprise."
IBM, the principal developer of LTFS, also offers LTFS software in a variety of editions for single drives as well as libraries. The company said their LTFS Enterprise Edition is designed to increase efficiency and reduce costs for long-term, tiered storage.
A number of backup software companies announced LTFS support this year, but it's far from widespread.
In May, Quantum announced that their vmPro virtual server backup software would support LTFS. This allows users to use vmPro with the company's Scalar LTFS appliance to back up directly to tape or to a Quantum DXi NAS disk appliance and then to tape. The LTFS appliance sits in front of tape and lets customers search for specific files. It appears as a network share and each tape appears as a folder. Veeam also added tape support for its virtual machine (VM) backup app -- Backup & Replication -- in May. However, Backup & Replication requires users to back up to a disk repository before sending copies to tape. The company said they chose this approach because tape is typically used for archiving and long-term retention rather than daily backup.
"I think many software companies have really taken their eye off the ball as it relates to tape," Woo said. "LTFS provides great opportunities for them to leverage the industry's lowest cost storage medium."
Is LTFS ready for enterprise action?
"There is a common misperception that the mere presence of LTFS will magically enable tape to become NAS-accessible shared storage, but in reality, there needs to be tools or solutions that can unlock the LTFS capabilities, making them generally useful," Schulz said. "This is where various vendors such as Oracle, Crossroads, Spectra, IBM, SGI, Quantum and NetApp, among others, are beginning to leverage the basic LTFS management capabilities and [are] adding support for the LTFS random directory and metadata information to quickly load tapes."
But, he went on to say that the level of support for LTFS available today varies. "Does it mean, work with different multi-drive tape libraries; does it mean grouping, blocking, stacking or containerizing data for placement on tape while interfacing with the LTFS management metadata?," he said, noting that users should "look beyond the checkbox and ask vendors what type of LTFS support they have or provide or enable beyond simply mentioning it."
Woo said he thinks we'll see software vendors putting more time into tape and LTFS over the next two years, and that LTFS will ultimately be preferred by large enterprises.
"For smaller companies, the emphasis will shift to tape-based service providers who can essentially create Amazon Glacier-like offerings through scale, with a focus on putting the data away for a long time at a low cost, rather than making that data available in the shortest amount of time possible," he said.
"In the end, with all due respect to LTFS, which I think is a good building block capability, it all comes down to how it is built into useful tools that can also be used and adopted by the masses versus kept or positioned for smaller special interests," Schulz said. "If the tape industry is truly interested in keeping tape and LTFS around for many years to come, they also need to unlock and open up some tools that position LTFS for broader adoption."