Vice President of Editorial
Published: 22 Oct 2012
The Linear Tape File System (LTFS) spec is more than two years old, but still only used in a handful of products. Maybe SNIA's new working group will inspire LTFS product development.
Let's skip the "tape is dead" rhetoric, disclaimers and all that other nonsense, and cut to the chase: If we've turned into data hoarders because complying with regulations means keeping everything forever or if we just think all that stuff must have some hidden meaning, we can forget about disk whether it's spinning away in our own data center or hiding behind a cloud.
It's not about performance or even preference; it's a simple economic equation. Hard disk drives (HDDs) are too expensive, use too much power, produce too much heat and take up too much space to be a viable storage medium for the tons of data we feel a need to squirrel away. Solid-state storage beats the heat and power downsides of HDDs and can require a fraction of the space, but no company's pockets are that deep.
Right after solid-state, the cloud seems to be the quick answer these days to storage dilemmas. And it's a good answer to the question, "What the heck should I do with all these files that nobody's looked at in years?" But despite Amazon's glacial price freeze that makes storage look too cheap to be true (maybe it is), keeping data in the cloud means paying for it over and over again for every day it's there, forever and ever …
Wow, tape isn't just looking good, it's starting to look darn modern. It's not a matter of whether it's a viable medium for mass storage; it's shaping up to be the only medium for long-term mass storage. It's fast, and its capacities have doubled or tripled over the past few years -- right now you can squeeze 5 TB of data onto an Oracle StorageTek T10000C tape, 4 TB onto an IBM TS1140 or 1.5 TB on an LTO-5 cartridge (and 2.5 TB LTO-6 is available now). And those are all capacities before compression. But you know about all those specs, so you shouldn't need to be convinced of tape's capacity and performance.
What you're probably waiting for is the missing link that will tie tape into the infrastructure a little more tightly and allow for greater accessibility and smoother data movement. But that's here, too, although if you don't follow the tape market closely there's a good chance you haven't heard about it. It's the Linear Tape File System (LTFS), and it's part of the LTO tape spec that was rolled out with LTO-5. LTFS reserves part of a tape for a file system so the contents of a tape aren't only more visible, but individual files can be accessed just as you would from a direct-attached disk or a NAS share. Sounds simple, but it potentially opens up a whole new realm of possibilities for tape-based applications.
Instead of storing all those seldom-used files on disks, stick 'em on LTFS-enabled tape. They'll look like they're as close as the nearest hard disk and can be accessed as easily -- it just might take a few moments longer. Sounds almost perfect for all those big data apps we keep hearing about, right?
LTFS is hardly new. It was introduced more than two and a half years ago. So where are all the products tapping into this cool resource?
Crossroads Systems was one of the first to recognize LTFS' potential and put it to practical use in its StrongBox archiving appliances. A handful of others have followed suit, with Atempo, FileTek, HP, QStar Technologies and Quantum among a handful of vendors with products that leverage LTFS.
Why has LTFS adoption taken so long and why are there so few products out there? The main reason is that it could be a disruptive technology; that is, it could disrupt sales of hard disk and solid-state storage systems pretty significantly. So disk vendors that don't also sell tape libraries aren't likely to pursue any sort of integration that would incorporate tape as a nearline tier. And they're probably equally concerned about the possibility of cloud storage services providers beefing up their tape-based file capacity and cutting back on HDD purchases. It's hard to figure who else might want to stall LTFS adoption, but the general lack of enthusiasm for this useful tech is kind of suspicious.
So LTFS languishes more than it flourishes, but that might change soon. The Storage Networking Industry Association (SNIA) recently cranked up interest a bit by forming an LTFS technical work group (TWG). The committee's mandate is "to broaden cross-industry collaboration and continued technical development of the specification." Admirable goals, of course, but SNIA is after all an industry consortium made up of storage vendors, so we'll have to wait and see if the TWG is a genuine effort to promote the spec rather than just a bit of lip service or, even worse, a "death by committee" move. The list of companies involved in the group includes LTO consortium members HP, IBM and Quantum, along with Oracle, but hopefully, more vendors will get involved and LTFS will find its way into more products. You can help speed up the process, too -- just ask your disk, tape or archive vendor to lay out their roadmaps for LTFS integration.
About the author:
Rich Castagna is editorial director of TechTarget's Storage Media Group.