On Mon, Nov 26, 2001 at 06:24:08PM -0800, Robert Kennedy wrote:
> > 
> > 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

I believe 1.4 was the first to have raidframe.  If you're upgrading, though,
1.5.2 would be the way to go.  

There may be another solution, though... the "ccd" driver supports
mirroring, and is in 1.3.  It's nowhere near as featureful as raidframe,
though, and I seem to recall it having some trouble with mirrors.

> 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?

No, in fact, I can confirm that it is indeed slower for writes.  (You're
doing twice as many).  Not *too* much different for reads, at least from
a user perception perspective... I haven't actually measured it.

> 
> > 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.

I can neither confirm nor deny, mostly because I haven't thought that closely
about it.  Rsync works well for what I use it for, which is admittedly
no really critical data.

+j
-- 
Jeff Rizzo                                         http://boogers.sf.ca.us/~riz