[Info-vax] Greater than approx 16GB disk leads to UNXSIGNAL crash

[Tad Winters]

On 5/25/2021 4:37 PM, arca...--- via Info-vax wrote:
> I wanted a 100GB disk (using SIMH) under OpenVMS VAX V7.2.
>
> That seems to be fine until I try to create a file. Admittedly I've only tried to create a file either using FTP or BACKUP, but as they're so disconnected, I assume that it's actually XQP (or something in the file system) that gets upset.
>
> I backed off my disk size and even 20GB triggers the crash. 16GB seems to be OK.
>
> Now OpenVMS beyond V5.5-2 supports single volumes of 1TB, so I'm surprised that a 16GB volume causes a crash.
>
> Does anyone have a real VAX with a real disk (> 16GB) successfully hanging off it? I do have some SCA-80 36GB disks but I've never successfully got them working on either a VS4000-96 or a VS4000-60, so I'm not in a position to try this out myself.

Get the latest SIMH and use the MicroVAX 3900 emulation.  I boot my V7.3
from a 1.5 GB disk and have about a 22 GB data disk and another 4 GB
disk.  I'm sure I've had simulations with larger drives.  This was just
one I put together to stick on a flash drive to show some coworkers.

I seem to recall a customer running V7.1 on a VAX 4000-105 with a bit
larger boot drive and certainly a 20 GB data drive.