Subject: Re: Boot from CD-ROM
To: Markus Illenseer <markus@TechFak.Uni-Bielefeld.DE>
From: Creed Erickson <creed@comet.com>
List: current-users
Date: 04/07/1995 20:26:51
On Fri, 7 Apr 1995, Markus Illenseer wrote:

>  Currently in the process to make a NetBSD CD-ROM I ask myself
> what is required to make it possible to boot from CD-ROM.
> 
>  Would it really be sufficient to have the entire / tree (base10) unpacked
> on the CD, along with devices node entries in /dev, boot with loadbsd -b
> and tell the kernel to boot from cd0 ?
> 
>  Does the kernel seeks for UFS or can it work with cd9660, too?
> 
>  If UFS - how about providing a multi-session CD, whereas the boot session
> is UFS?
> 
>  Questions over questions... any takers or pointers please?

And you didn't even touch on what could potentially be the most complex
problem: What to do if something decides to swap. Let's face it, a virtual
memory system assumes there is a writable store out there somewhere and a
CD-ROM does not fit the bill. I imagine that you can avoid swapping under
controlled conditions with N Mb of ram, but is N going to be small enough
to be practical?

It strikes me that to get enough of a system up, partition, format and
install on to a hard drive, while guarenteeing a no-swap condition, you're
likely to exceed a reasonable memory requirement. I have no empirical data
to back that up, so it's possible I'm suffering a rectal-cranial
inversion. 

---
Creed Erickson                                            creed@comet.com
Livermore, CA 94550-5822
USA                                                Voice: +1 510 373 7615