> > The idea is this: I have two disk drives that are identical except for
> > the data stored on them. One of them is my main drive, and the other
> > is my backup drive. Periodically I would like to back up the main
> > drive to the backup drive.
> 
> 1) You can mirror the two drives using raidframe...

Does NetBSD 1.3 have raidframe? "man 4 raid" says "no entry for
raid..." on my machine (running 1.3/i386). This sort of sounds like
the perfect solution, though, except for that. Is it going to force me
to upgrade to a later version of NetBSD? Another concern is that my
machine is already pretty slow, and I'm concerned that the extra time
spent doing twice as many writes to disk might be noticeable. Can
anyone reassure me that it wouldn't be?

> 2)  You can use rsync...

rsync seems fundamentally ugly to me because it depends on good luck
of checksums to work. When there are checksum collisions, it can fail
silently and heinously. Not a common occurrence, but still a
fundamental weakness IMHO. Hopefully someone will correct me if I'm
showing some sort of misconception about this.

	-- Robert