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Re: installboot is broken

On 03/24/2013 08:08 PM, Mark Pizzolato - Info Comm wrote:
This issue CAN and SHOULD be fixed.  However, there is a fundamental chicken 
and egg problem here in that every available NetBSD vax ISO image going back to 
the earliest available (NetBSD 1.6.2) are all missing this boot block on that 
media.  Clearly no one has attempted to install any version of NetBSD on a 
legacy VAX (one which boots without the aid of a ROM based VMB).
I have done that on all of them; since I actually wrote the code :-)
This issue came to light due to efforts to use NetBSD with the latest simh's 
new VAX simulators (VAX 11/730, VAX 11/750 and VAX 8600/8650).  All of these 
systems use VMB to initiate the bootstrap process and since the disk being 
booted doesn't contain a Digitial ODS2 disk structure, they boot using they 
achieve a boot using the bootstrap code provide in sector 0 of the device being 
booted.  The systems with ROM based VMB have built in code in the ROM VMB to 
use the pointers describing the bootstrap location in sector 0 to directly load 
the rest of the bootstrap (usually from sectors 1 thru 13) and dispatch to that.
You are not supposed to use VMB on those big machines. You should load boot directly from the console media.
This is how all BSDs always have worked.

-- Ragge

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