From: jones@churchill.ColumbiaSC.NCR.COM (Brian.Jones)
Subject: Re: SCSI disk upgrade for 3450
Organization: NCR Corp., Columbia SC
Date: Tue, 26 Jan 93 12:08:58 GMT

In article <108@shady.UUCP> kevin@shady.UUCP (Kevin Smith) writes:
>In article <1993Jan25.161616.8596@ncrcae.ColumbiaSC.NCR.COM> wescott@yesac.ColumbiaSC.NCR.COM (Mike.Wescott) writes:
>:>In article <C1Eyyw.ApA@casper.cs.uct.ac.za>, ken@casper.cs.uct.ac.za (Ken MacGregor) writes:
>:>
>:>|> We wish to upgrade the disk storage on our NCR 3450.  According to the
>:>|> local distributor the ONLY disk >1Gb which is approved is the Seagate
>:>|> model ST41601N and this requires a proprietary NCR firmware upgrade so
>:>|> cannot be sold direct to us.
>:>
>:>The SCSI subsystem is written, as best we know how, to accommodate
>:>generic SCSI peripherals.  Sometimes, however, we find bugs or other
>:>problems in these peripherals that the vendor will fix by making an NCR
>:>only change to their firmware.  I know of no contractual requirement
>:>(***disclaimer*** but it's not my job to know), that prevents a vendor
>:>from releasing that firmware to other customers.  I can think of
>:>several support issues whereby a vendor would not want you to have a
>:>firmware set that was "non-standard".
>:>
>:>|> All the other computers in the dept - Sun's, SG's Vaxen etc. permit
>:>|> upgrade by user purchased SCSI disks for which we enjoy the eductaional
>:>|> discount.  There is no educational discount from NCR is SA.
>:>
>:>|> Does anyone have any knowledge of other disks which can be used to
>:>|> upgrade the 3450.
>:>
>:>There is a good chance that a given drive will function correctly in
>:>the 3450.  There is also a good chance that you'll have a hard time
>:>getting support if something goes wrong.  And some of these devices do
>:>have bugs that make them unusable on the 3450, whereas other "specials"
>:>merely change some of the defaults (i.e. spare sector allocation
>:>strategy).
>:>
>:>--
>:>	-Mike Wescott
>:>	 mike.wescott@ColumbiaSC.NCR.COM
>:
>
>Nice to hear from you guys in Columbia!
>
>I know for a fact that HP 660MB and 1.2GB drives work fine.  I do believe
>that the Seagate drives are the only ones that NCR support will cover and
>putting unsupported drives in the cabinet may void NCR support.
>
>I also am pretty sure there is no special firmware issue with the Seagates.
>I can check this and will post what I discover.
>-- 
>	    | Email - !shady!kevin uunet!shady!kevin kevin%shady@uunet.uu.net
>Kevin Smith | Voice - (+1) (908) 874-7980
>	    | Mail  - ShadeTree Software, Inc., 192 Capricorn Dr. #10,
>	    |         Somerville, NJ  08876, USA

The reason that this special Seagate firmware is required is to fix a
timing problem with the drive.  It did not come back and respond quickly
enough after a Bus Device Reset Command.  The 3450 firmware issues this
command on a system reset to get the device back to asynchronous mode
so that system firmware can talk to the drive.

On the matter of putting in generic drives (standard disclaimers apply) this
should be OK as long as the drive is SCSI II compliant.  The things
you should do to the drives are to make sure the terminators are removed
and that the disks are strapped to spin-up on command.  Be warned,
however, that this may void your warranty (I'm was just the lowly developer
on the 3450 firmware).


-- 
_____________________________________________________________________________
Brian M. Jones                   NCR - Networked Computing Resource of AT&T
Brian.Jones@ColumbiaSC.NCR.COM   Midrange Computer Products Division-Columbia
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