Jessica Delage April 28, 2021 at 11:45 AM 6 min read

Need to Consider a LTFS Hybrid Storage

Do you think that Cloud Storages are always the right solution ? 

In this article, we explain cases where a LTFS solution bring value in your activities.

It's hard to beat the economics of magnetic tape when it comes to archiving or backing up large amounts of data at low cost . The storage medium itself is cheap, offers high capacity, and it consumes no power.

LTO-8 Value - TCO Graph for LTO-8 vs Disk

Source : ESG Lab and Storage Solutions -  LTO-8 Value - TCO Graph for LTO-8 vs Disk

But there are drawbacks :

  • Accessing data stored on tape can be slow,
  • Traditional tape archiving and backup systems tend to be highly proprietary: the way the data is stored, and the database containing the tape indexes that allow you to access data is unique to each vendor. That means tapes made with one system can't be used in any other.



In our today world, vendor locking is not anymore an option. It is to address this issue that Linear Tape File System (LTFS) data format was developed by IBM. The key feature is that LTFS is open and independent of any separate database, so tapes that use the data format can be used in any system that works with the format, from any vendor.

But perhaps more importantly, storage systems running the appropriate LTFS software can also present a standard file system view of the files stored on the tape in LTFS format, just as if they were stored on traditional spinning disks or flash media. That's important because it means users can drag and drop files or simply click on them to access them in the normal way.

Proprietary LTFS software has been developed by IBM for use in its tape drives, and there are also several open source solutions developed by the likes of Oracle, Quantum and HPE. LTFS software is also commonly used with cheap Linear Tape-Open (LTO ) tape cartridges.

Large file storage

LTFS systems have been particularly popular among video production companies for storing huge media files and now adopted by others industries such as research, life science, ...

Cloud alternative

It's certainly true the cloud-based archiving services offer tremendous – and scalable – storage capacity at a low price, with effectively no power requirements (in your data center). But the cloud is not a practical solution for archiving large media files. "When you need the data back, the time involved in transferring these files makes it usually impractical". 

High performance tape

We've established that LTFS libraries are cheap and scalable. But by combining some disk (or flash) storage – used as a fast access cache – with LTFS tape systems presenting a standard file system, it's possible to create a hybrid storage system that is fast and offers vast unstructured data storage capacity and very low cost.

One way is to use a hybrid LTFS tape/ disk solution designed to offer capacity for data archive and data protection. It looks like a standard NAS appliance, and contains both disk and LTFS tape storage, with policies that can be applied to govern how data is treated.

Protected storage
All the data is stored on disks for fast access, but automatically backed up to LTFS tape to provide a backup copy that can be accessed easily if needed.

A hybrid system can also be used to provide automatic tiering, using policies to determine where data is stored.

For example, in a research environment a new DNA Genome can be stored to disk and accessed by BioInformatician very fast. After a set amount of time dictated by policy – perhaps 90 days – the data is unlikely to be required again and can be archived within the system.  This simply involves moving it from disk to tape.

Since it is stored in LTFS format it can be read back by any other LTFS system.