How will tape's role change?
There are certain things that disk is very good at: fast restores, getting initial backups onto disk very rapidly and reliability. Those are all advantages in the disk space.
Tape tends to excel in two areas: low-cost storage and performance. What we're recommending to our customers is to front-end the backup infrastructure with disk. That's where they would handle most of the restore requests for files or messages -- object-level restores like that.
Eventually they'll be migrating that data after it ages back to a less costly tier, which would be tape. If they're going to be running most of their server-level restores from that level, they can actually get better performance out of tape than disk. The fact that you can keep those tape drives streaming for that kind of activity means that the tapes will perform that much more reliably.
30 Jul 2008