Richard Rauch wrote:

[ ...]

> My options seem to be ccd and RAIDFrame.  Is there a discussion
> somewhere of the tradeoffs between these two?

grab one or both these tools and have a play yourself. If you test
with a size and I/O mix that matches your particular usage you should
have a better idea than most articles on the net can provide. If it
might become important check the performance as you fill the disc
to 90-100%. My experience has shown the BSDs do quite well.
http://www.iozone.org/
http://www.coker.com.au/bonnie++/

> Secondly, I don't suppose that it is possible, but I'll ask:
> Is there some way that I can set up a filesystem to let me
> incrementally add disks?  (Maybe some RAID level?)  I gather

vinum might be what you are looking for here. searching for
Logical Volume Manager or LVM should get you some hits.

> that FFS, at least, tries to scatter file blocks around the
> disk, so it may not be easy, and perhaps there is no facility
> for what I want.  My reason for asking is that I might either
> leave the second disk in its packing for now, or I might use
> it for redundancy.  But when the first 120GB fills up, I might
> like to be able to use the second 120GB to double my space.
> 
> 
> Lastly: This is on an i386.  I had the vague memory that some people
> had reported problems with large disks.  I know that the OS kernel
> needs to be located on parts of the disk that BIOS can find in
> order to boot.  I searched the lists for this topic but came up
> with fewer matches than I expected, so I suspect that I missed
> some.

difficult to know which HD limit. I expect the recent 120GB limit,
fixed by 48bit LBA.

> Assuming that BIOS finds the kernel and boots the OS, can I
> expect to use the full 120GB under NetBSD without any problem,
> no matter how old the PC?

I'll leave this to the netbsd experts.

Simon