I've got many requests from business partners to helping them answer this kind of question.
For me, it's a simple answer but for someone whose doesn't have much experience with tape.
It will be hard for them to explain.
The main reason is still a "Total Cost of Ownership - TCO".
Based on my translate article "D2D is Not Enough" to Thai language.
Here are the list of tape technology advantages over disk and reason why it's still useful in the storage solution as for the long term backup and archival data protection.
Cost, Raw $$/GB, the main reason
Tape cost is about 1/15 to 1/20 of disk cost
Tape $.75-$3.5/GB
Enterprise disk: FC, SCSI, FICON, ESCON; $50-$70/GB
Mid-range disk: FC, SCSI; $20-$35/GB
Low cost disk: SATA; $5-$15/GB
Other hidden expansion cost:
For tape, just add tape cartridges.
For disk, not just only hard drives, the array cost and more physical disk for RAID are the hidden cost.
Other Tape technology advantages
- Removability
- Environmental (power consumption)
- Archival life
- Non-FAT data structure, no virus attack on tape
- Security
- WORM support
