[Info-vax] Exploring a hard drive on a new Vaxstation

Johnny Billquist bqt at softjar.se
Sun Jan 28 21:14:49 EST 2018


On 2018-01-29 01:31, Bill Gunshannon wrote:
> On 01/28/2018 06:39 PM, DaveFroble wrote:
>> Cliff Miller wrote:
>>> I have a Vaxstation 3100 Model 30 which came with an RZ23 hard drive. 
>>> I access the system with a serial console cable.
>>> The system boots to the >>> prompt and self-tests just fine.  When I 
>>> try to boot from the hard drive, however, it returns "File not found."
>>> I am reluctant to initialize the drive and start from scratch as I am 
>>> curious to see what was on it.
>>> What are my options for being able to explore the hard drive?
>>
>> I'd be a bit surprised if there are still any working RZ23 drives.
> 
> Surprise!!!  I have a number of them still.  :-)

I might have one or two as well.

>> Another note, the VAXstation 3100 systems can use a boot device of no 
>> more than 1 GB, if I remember correctly.
> 
> True, I checked it in the FAQ because I admit my memory is flawed.

And that is a truth with some reservation/caveat.

There is actually no problem for the device to be bigger. The issue is 
that the device driver in the boot firmware uses SCSI commands that only 
have a 21-bit field for block number, and thus cannot address any blocks 
higher than that. So, in order to boot, all the disk blocks needed to be 
read by the firmware needs to be within the first 1G, or else bad things 
happen. But, as long as you can guarantee that the boot firmware does 
not want to access any block above the 1G limit, you can boot from any 
size disk.

With VMS, this is hard to guarantee. With NetBSD, this is easy to 
guarantee. So, for NetBSD, just make the 'a' partition (root) no more 
than 1G, and you can use it just fine.

Once the OS has started running, it will no longer be using the driver 
from the firmware, and then the OS can easily access all of the drive.

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol



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