Fred,
I think what surprised me about it was that a reading of the UC07 installation
manual led me to believe that the "emulation" feature of the UC07 created an
"special" structure on the SCSI HDD. The fact that Emulex didn't do
something "strange" made me appreciate the them even more ;-)
Lyle
On Tuesday 06 January 2004 12:08, Fred N. van Kempen wrote:
> On Tue, 6 Jan 2004, Lyle Bickley wrote:
> > Here's another "interesting" point - a VMS HDD created by the Emulex UC07
> > or KZQSA is compatible with either the KZQSA or UC07.
> >
> > I could hardly believe it - but the same SCSI HDD created from either
> > will boot and run VMS from either...
>
> Well, a SCSI device does its own low-level formatting and bad
> block management and interleaving, so, pretty much is a box full
> of data blocks to the controller. So, the controllers only have
> to address those blocks, and nothing else- this would indeed
> allow to "share" the layout between controllers, as is quite
> normal for SCSI devices these days.
>
> Although the UC0x controllers use KDA50 emulation, they do this
> towards the *host*, not the *device* end, so probably don't do
> anything weird at the device end that would make them incompatible
> with the other controllers, such as the KZQSA. Which, if memory
> serves me right, was just an NCR 5340 or 5380 atop a Qbus bus
> interface..
>
> --f
--
Lyle Bickley
Bickley Consulting West Inc.
http://bickleywest.com
"Black holes are where God is dividing by zero"
Received on Tue Jan 06 2004 - 14:38:59 GMT