Starting OpenBSD read-only from cd-rom?

[Michael Hilscher <misc-openbsd@michael-hilscher.de>]

Hi,

i like to burn an limited cd-rom system (with right configured
networksetup, ssh and some admin tools like sed, vi and so on) for
remote repairs if system wont start or if i like to do some manually
fsck works on it.

I think i'll take cdrtools-1.10p1.tgz for cd-creation. But (and this is
my real question ,-) how can i change the boot device remote from wd0 to
cdrom? The cdrom will stay in player so i cant boot from cd-rom directly
cause at restarts shall boot (usually) the "harddisk" not the "CD-Rom"
System ...

So i'm actually searching for an OpenBSD Bootloader which allows Entrys
for more than one OpenBSD System and can start systems on harddisks
aswell as on cdrom's. BTW: OpenBSD needs to get installed on an primary
Partiton - do i need to take care about this, during iso creation or
burning of my cdrom?

greetinXs,        
Michael Hilscher 
-- 
Would Mozart have been more productive if he had scribes to help him, a
secretary and a CEO to lead his way? -- Linus Torvalds