Backing up to tape

Tape is the medium of choice for backing up data on Web servers and other large computers. It's less popular on personal computers because tape drives tend to be expensive, but it has advantages that you shouldn't overlook. Tape is reliable, economical, and reusable, and it's the only backup medium with enough capacity to back up an entire hard drive at once - short of a second hard drive, anyway.

The low cost of tape makes it feasible to keep several generations of backups. If you need to refer to an old version of a file or recover a file that you deleted weeks or even months before, that can be a lifesaver.

When you choose a tape drive, look for one with enough capacity to back up your entire hard drive on one tape and enough speed to do it in a time that you consider reasonable.

As with disk drives, choose a tape drive with a type of interface that is appropriate for your computer. Drives are available with EIDE, USB, and SCSI interfaces.

If you decide to buy an external tape drive, your choice of interfaces is limited to USB and SCSI. There's a particular reason why you may prefer an external drive: If your computer needs repair, you can more easily move an external drive to a loaner system to restore your data and resume your work. Tape drives are not standardized, so you can't necessarily read your tape on any loaner that has a type drive - even assuming that you can find any loaner that has a tape drive!

Unlike the various types of disks, a tape drive must be read and written by a special utility program. Several software publishers sell such backup utilities. Check with a given utility's publisher for information about what devices it supports.