Re: installboot is broken

[Johnny Billquist <bqt%softjar.se@localhost>]

On 2013-03-24 21:51, Anders Magnusson wrote:
> 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.

That is how we used to do it, a *long* time ago.
I'm not sure I even remember how to create a standalone boot to be put 
on the FE anymore. There are definitely no procedures left around to do it.
VMB can boot Unix system, and Ultrix uses the same thing. There is one 
specific bit in R5 that tells VMB to boot something using the boot block 
instead of trying to boot VMS.

        Johnny

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Johnny Billquist                  || "I'm on a bus
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