> > The BA350 storage shelves are narrow-only. You can't use the
> > wide SBBs in them. A BA356 would probably be a better choice.
> > A lot of the newer wide SBBs use SCA drives.
> >
> > The BA35x use a proprietary backplane, not an SCA backplane.
> > Fortunately, you can find the SBBs cheap.
> > --
> >
> Yeah, probably the same backplane that's in the older AlphaServers here...
I think the backplanes in the AlphaServers are wide SCSI.
> So, to see if I understand you correctly...
>
> - The SBB is the tray for the HDD...
The SBB is "Storage Building Block", with the storage element inside.
> - The SBBs for use in the 350, have a 50 pin connector, none have the SCA...
Yes. The BA350 and BA356 have the same backplane connector, but the
wide SBBs can not be seen when installed in a BA350. However, narrow
SBBs can be used in a BA356.
> -- If so, I wonder if there is room inside the tray to fit a SCA 80-50pin
> adapter?
Usually not. There isn't much room in the 3.5" SBBs. Maybe, if the
SCA converter was real small, it may fit.
Another thing to consider is the ID selection cables in the non-SCA
SBBs (both narrow and wide) are specific for each installed drive,
so unless the jumpers are the same you'll have to hard-code the ID
and make sure you avoid ID conflicts. Of course with SBBs with an
SCA adapter that's not a problem (which is why I prefer them, so
installing a bigger hard drive is no problem).
> -If I want to use narrow SCA-80 drives in a Digital Storage Shelf, I should
> look for the 356 and SBBs for that?
It would be easier. With a BA356 you can use a BA35X-MG narrow
personality module if you want to connect to a narrow SCSI bus
or use a wide-narrow external SCSI cable. The only drawback
(which may not be an issue for you) is the HSxY0 raid controllers
don't work well with a wide-narrow external cable.
--
Eric Dittman
dittman_at_dittman.net
Check out the DEC Enthusiasts Club at http://www.dittman.net/
Received on Tue Feb 12 2002 - 10:34:13 GMT