On 2019-07-12 20:59, Mark Pizzolato wrote:
On Friday, July 12, 2019 at 11:27 AM, Johnny Billquist wrote:
As far as I am aware, it was only some models in the 3100 series that used the
shorter SCSI commands in the boot rom, which caused issues with the boot
disk. However, I'm not sure that exact thing is the problem.
You might very well have some display issues that pop up in the boot monitor,
even though the system will boot perfectly fine from a larger disk.
On the older VS3100 systems (without large disk boot support), things would
boot fine on larger disks as long as the pieces of OS code that are loaded in
the early stages of the boot all happen to be located early enough in the disk
drive. Since you can't guarantee that all the needed files would be located
early in the drive large disks were "not bootable".
Actually, the lack of guarantee would certainly be true for VMS systems
that only could have a single file system on a particular drive, but Ultrix
systems should be able to have an a partition that was sufficiently small to
guarantee the ability to boot.
Yes, with Ultrix (or NetBSD) the problem is essentially non-existent. I
was running NetBSD/vax on a 3100 for several years, with a large disk,
and no problems.
Also, as soon as you're out of the boot rom code, there is no
limitations either. So it's only for the early stages of the booting
where this ever is a problem.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: b...@softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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