> 
> I use the parameter I get under vms to write the disklabels.
> When boot from the ra(1,1,1) and then mount the root device on ra5
> I get the message
> udb1 loss interrupt
> reset uda0 
> Process(pid 0) got signal 11
> 
You have a third-party disk controller which do not work exactly
as the DEC controllers. It emulates a RA81 with a different 
geometry, therefore the other sizes. The crash is because of that
the controller generates a uba reset, and ubareset's do not
work as they should yet.

-- Ragge