LTFS tape NAS: What it is and how to build it
Linear Tape File System (LTFS) offers the chance to build nearline storage with the cost profile of tape and the access times of NAS. This guide walks you through LTFS and tape NAS
Introduction
In storage, cost is everything. So, imagine a storage medium with the frugal cost profile of tape and access times ofNAS. Well, it already exists. Since 2010 the Linear Tape File System (LTFS) has allowed access to tapes as if they are spinning disk. Part of the LTO-5 tape format, LTFS partitions the tape, with one containing indexing information for all the data on the cartridge and the other contains the actual data. Marry this capability to a hardware NAS protocol front end with a disk cache and you have the potential for rapid access to massive amounts of data held on tape.
Tiered storage is now mainstream. We have super-rapid flash for virtual machines and their data; Fibre Channel and 15k SAS for other fast access use cases. After that there is high-capacity SATA for bulk data, but here is where LTFS could start treading on the toes of disk vendors. That’s because, in some cases, where the use profile of data requires long retention and infrequent but relatively quick access, LTFS tape now rivals large capacity SATA as a nearline store.
Maybe that’s why LTFS has failed to set the world on fire; there are just too many disk vendors who see it as a threat. Nevertheless, LTFS is worth looking at. And in this ComputerWeekly.com Guide you’ll find articles on why LTFS should be taken seriously and explanations of how tape NAS works and who sells products.
