[Info-vax] %SYSTEM-F-ACCVIO after fresh VMS installation

[John Wallace]

On Jan 30, 9:06 am, John Wallace <johnwalla... at yahoo.co.uk> wrote:
> On Jan 30, 2:55 am, MG <marcog... at SPAMxs4all.nl> wrote:
>
> > On 30-1-2012 3:40, Jeremy Begg wrote:
>
> > > I'd say your DS10 hardware is kaput. It could be anything in the path
> > > from the disk to the CPU. And RAM can fail too.
>
> > If that's so, how is it that the entire installation procedure goes
> > well, without a single error and that all the hardware passes the
> > tests and exercises in the SRM environment?  If there would be some-
> > thing broken in the CPU and/or RAM, wouldn't things also go terribly
> > wrong there?
>
> >   - MG
>
> It's possible for only a small part of RAM to be broken, and for many
> operations to not use this RAM. So if in one system config the broken
> RAM is unused, no fault would be observed. In a different config the
> RAM may be used, and symptoms would show.
>
> "Opcode reserved to DEC" (aka "Opcode reserved to OpenVMS") doesn't
> sound like the usual likely symptom, but...
>
> I've lost track of whether the problem follows the memory or follows
> the motherboard or follows the disk. Work that out and you may get
> somewhere. This is joukj's suggestion wrt moving the disks. Bear in
> mind that if dubious memory was in use when you did the OS install,
> even if the current symptoms didn't show at that time, the resulting
> installed image may be dubious too.
>
> Another item I might add to the "To Do" list would be to put the
> suspect RAM in a box where it can be tested with MemTestx86 or similar.

"In a different config the RAM may be used, and symptoms would show."
should read
"In a different config the RAM may be used, and symptoms may or may
not show immediately. If the RAM error led to an invalid instruction
being executed, that would show right away. If the RAM error led to
invalid data which propagated silently e.g. led to corrupt data on a
disk where VMS was being installed, that may not show until much
later."

It's a bit unlikely but not necessarily impossible.