From: aris@unisup1.uucp (Aris Stathakis)
Newsgroups: comp.unix.sysv386
Subject: Re: SCSI on Xenix
Date: 12 Aug 92 06:39:28 GMT
Organization: Lasernet (pty) Ltd.

In <BsK76x.JB8@gator.rn.com> larry@gator.rn.com (Larry Snyder) writes:

>vid@zooid.guild.org (David Mason) writes:

>>I'm currently running Xenix 2.3.2 with two ESDI hard disks. I want to upgrade
>>my drives, but rather than investing more money in ESDI drives I thought I
>>should consider selling them and replacing them with one largish SCSI drive
>>instead.

>Good idea -- how about multiple SCSI drives?

>>After contacting SCO I found out that I would need to upgrade to Xenix 2.3.4.

Why not upgrade to SCO UNIX and *KEEP* your ESDI drives and *ADD* a SCSI
controller with up to 7 extra hard drives?  There is a Xenix to UNIX upgrade
available.

>>1. Would it be difficult to move our system from 2.3.2 to 2.3.4? We have quite
>>a few custom programs installed. What are the major differences between 2.3.2
>>and 2.3.4?

>I can't speak on Xenix since I haven't used it in several years (ie: 2.3.2
>comes to mind as the last release that we were using) -- however, Xenix
>binaries run just fine under Unix

You should not have any compatibility problems between SCO UNIX and SCO Xenix
except for device drivers.


>>2. I have heard that the Xenix SCSI drivers aren't very good, specifically
>>that they aren't very fast. I'm probably going to purchase the Adaptec 1542B
>>controller if I go through with this, would there be a noticeable speed
>>improvement over the present ESDI drives using a WD 1007V-SE2 controller? I
>>assume the drive seek times will be approximately the same (~20ms). 

>I thought the 2.3.4 release of Xenix contained a "high performance" SCSI
>driver..

The 2.3.4 Xenix does have better drivers, but they don't compare to the
UNIX 3.2v4 drivers.

>You should see a noticable difference between the SCSI and ESDI drives 

For sure...

>>3. Since SCSI drives can work independantly, would I be better off going with
>>two drives, and using one for the spool directory?

>yes - as mentioned above


Yes multiple SCSI drives are always preferable.  Even more so if you use 
disk array software like 1776 which stripes/spans/mirrors/duplexes SCSI
drives.  Now that REALLY improves performance, but only runs on UNIX, not
SCO XENIX - and only with Adaptec controllers at the moment.

>>5. Can I easily combine IDE with SCSI drives? I would like to have two IDE
>>drives and two SCSI drives. Would the IDE drives interfere with (3) if
>>applicable?

>I don't know if it is easy to do -- but I would think it would be quite
>possible

You should be able to do this under SCO, but since you already have an ESDI
controller, why not leave that in the machine and add the SCSI controller?

>>One final question, someone inquired about a version of X Windows for Xenix.
>>I'm interested as well if it exists. I would also like to network an MSDOS
>>system with the Xenix system, and would prefer to do so without purchasing the
>>SCO TCP/IP software. Is the required software available in a public domain
>>version or am I stuck paying for it? 

You can get SCO X-sight for SCO Xenix, or I've seen Public Domain alternatives
(though I've never tried them) which might do what you want.

About networking an MSDOS machine to a Xenix system - well it depends on what
exactly you want to do.  If you just want remote logins, TCP/IP might be best
in the long run.

Aris

-- 
Aris Stathakis        Tel +27 11 887 4220 | 
SCO Unix Support      Fax +27 11 887 1141 |     " Ni, Peng, Nooooowom. "
UniNet - A Division of Lasernet (Pty) Ltd |_________________________________
Internet:   aris@unisup1.UUCP      Bang: uunet!ddsw1!olsa99!unisup1!aris
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