Tape with LTFS has several advantages over the other external storage devices it would typically be compared to. First, tape has been designed from Day 1 to be an offline device and to sit on a shelf. An LTFS-formatted LTO-6 tape can store 2.5 TB of uncompressed data and almost 6 TB with compression. That means many data centers could fit their entire data set into a small FedEx box. With LTFS the sending and receiving data centers no longer need to be running the same application to access the data on the tape.
Tape allows for a clean sweep of data that simply doesn't need to be on any form of disk but still needs to be kept. The cost and capacity of tape makes these 'just in case' copies very affordable.
As I noted in my article "Comparing LTO-6 to Scale-Out Storage for Long-Term Retention," in these situations tape is an ideal storage type. Data on tape can still be automatically scanned for durability and it certainly meets the cost-effectiveness requirements.
... All the drivers that started the replace-tape-with-disk movement in the first place - reliability, performance, portability and off-site data movement - are now liabilities in a disk only strategy.
Right now our blog on the presence of tape at EMC World is seeing twice as much traffic as all the other EMC World related content. Why? Many of our readers are coming to the obvious conclusion that tape, despite the negative marketing, is still an optimal way to protect and archive their information.
Now clearly this advantage is when the data on tape has been found and just needs to be transferred back. You need to add a minute or so of seek time to find the data. On large transfers, though, tape should outpace most disk systems. From an ingest perspective, LTO-6 and other enterprise tape formats may be unrivaled when compared on a single unit basis.
