Subject: Again: Booting a Vax-Server 3100 with NetBSD-1.4
To: Jan Mueller <j.mueller@ginko.de>
From: Bertram Barth <bertram@gummo.bbb.sub.org>
List: port-vax
Date: 06/19/1999 08:20:40
Jan Mueller writes:
> So i put the rz24 out of the vax and connected it
> to a Pmax (NetBSD-1.3.3) and labeled it :
> # disklabel -w -B -b /usr/mdec/hpboot /dev/rz2 rz24

layout of bootblocks and thus the way disklabel writes the binary
data to disk is specific to the different architectures. I don't 
know the PMAX layout, but there's little chance it's identical to
the VAX layout. Ie. for VAX partition information is stored in the
middle of the bootblock thus VAX bootblocks hold a area of zeroes 
whichs act like a "window" or "hole" which preserves partitions
when being written by the correct version of disklabel. If a "foreign"
disklabel doesn't know about such things, the disk won't be bootable.

> After that i newfs'd the partitions and untarred 
> the binary-sets.

newfs creates and writes data in host-byteorder. VAX is little-endian,
PMAX is big-endian. Thus filesystems are not interchangeable.
Away from the different layout of bootblocks filesystems created on
i386 and VAX would be interchangeable.

> Booting the disk in the vax gives this repeating error:
>  83 BOOT SYS
> ?50 SCB2NDINT, DKA200
>  85 RESTART SYS

I'm not sure at which stage booting fails, but even if first-stage
works the second-stage boot will fail since the VAX won't find the
/boot program since filesystem access and inodes are involved wich
are in host-bytorder and thus invalid for VAX. The above error
might result from this. In short: it just doesn't work.

> Isn't it possible to create a bootable disk for a vax with a
> Decstation or do i need a pmax-version of edlabel ?

IMHO it's impossible (at least without lots of modifications)

> Or is my machine (VaxServer 3100, Model: DJ-31ESA-A, CPU: KA41,
> Series BA42B) not supported at all ?

With correct bootblocks/filesystem it should just boot/work.

Ciao,
	bertram