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

[arca...@gmail.com]

On Wednesday, 26 May 2021 at 16:33:54 UTC+1, Stephen Hoffman wrote:
> If this is a production project, 

If this is production, then I'm doing something illegal ... or maybe OpenVMS licensing has moved on. I'm not aware of any way to legally run OpenVMS on SIMH. I guess HP *could* issue a commercial licence for SIMH, but I'd be pretty surprised if they ever had!

> 
> As for your testing assumptions, ~nobody back then was looking for 
> these sorts of issues, 

I'm just surprised that the size was supported without any testing at all. 4GB was common back then and 8GB existed. Just one further doubling would have come close to hitting this issue (assuming it is real and not just something sent to try me).


> production AlphaServer configurations featured. With your data-access 
> project, you're back nearly a quarter century. That's a long time in 
> the IT business. 
I know. 

> If this is a hobbyist data-recovery project, have at. 
It is, and rest assured I will :-)


> recommend Alpha or Alpha emulation here (reports here that AXPbox works 
> reasonably well, IDE bugs aside), as Alpha has the advantage of a 
> couple of decades of updates that your OpenVMS VAX configuration lacks. 

I will have to give AXPbox a spin some time. However, my set of Alpha OS releases is even more limited (only V6.2 ... donations gratefully accepted :-)) so I'd actually be going backwards in time.

> And here, I'd wonder if this is a TCP/IP Services bug. TCP/IP Services 
> prior to V5 (UCX$) wasn't entirely stable, 
Sadly the crashes have dropped off my my terminal's scrollback buffer so I can't currently offer any evidence. My first assumption was to blame UCX's FTP too. But then I did the equivalent of:

$ BACKUP DUA2:[000000]FOO.BCK/SAV DUA1:[FOO...]  ! DUA1 is ~100GB at this point

and instantly hit exactly the same crash.

I rather suspect that:
$ copy tt: dua1:[000000]test.txt
hi
^Z

will do exactly the same ...



> and V5 (TCPIP$) and later 
> has had and has its issues. DEC sought OSI, and OpenVMS IP support 
> never recovered.

True. But DECnet VAX Extensions/DECnet OSI/DECnet Plus (or at least the PSI/WANDD bits thereof) kept me in REO for a while and that would probably never have happened if IP had ruled the roost in DEC. So I'm not complaining :-)

Antonio