Information Technology Reference
place? Or automatically rotate among several destination disks?
These are just a few examples of the kinds of control you give up
with Time Machine, but which you could gain, if you need it, with
other backup software.
Bootable duplicates: Although it's possible to restore an entire
disk from a Time Machine backup and then boot from that disk,
you can't boot directly from a Time Machine backup—and that
restoration process could take hours or even days. So Time Machine
should be considered a companion to a bootable duplicate, not a
substitute for one.
If any of the foregoing makes you think Time Machine isn't a good
fit for your needs—or if, like me, you want to use Time Machine but
supplement it with other backup software—don't worry; there are
many other options to choose from. I turn next to the features to look
for when exploring versioned backup software, and then discuss a few
particular programs I can recommend. However, if you're satisfied
with Time Machine, you can skip directly to Choose Backup Hardware .
Explore Backup Software Features
I've tried more than 100 backup programs, and I've read Web sites
and instruction manuals until my brain went numb. Evaluating any
given program on its own is hard enough, but comparing them is
even more challenging. For one thing, because software developers
use terms such as “incremental,” “versioned,” and “backup” differently,
you may think you're getting certain capabilities that later turn out to
be missing. For another, even when two programs have essentially the
same feature, each may implement it in entirely different ways.
In the next several pages, I describe features that may be significant
to you in choosing versioned backup software, and in the Online
Appendixes , I provide a table that lists the features found in current
versions of many backup programs, using my preferred terminology
(which may or may not match what a given application's marketing
materials say). You may find it helpful to jot down the features you