Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!asuvax!mcdphx!mcdchg!ddsw1!karl
From: karl@ddsw1.MCS.COM (Karl Denninger)
Newsgroups: comp.unix.xenix
Subject: Re: sector interleave
Summary: Successful reformats (nondestructive) with Speedstore
Keywords: query, iau, interleave, WD1006
Message-ID: <1989Oct2.135014.689@ddsw1.MCS.COM>
Date: 2 Oct 89 13:50:14 GMT
References: <358@mplex.UUCP>
Reply-To: karl@ddsw1.MCS.COM (Karl Denninger)
Distribution: na
Organization: Macro Computer Solutions, Inc., Mundelein, IL
Lines: 35

In article <358@mplex.UUCP> fff@mplex.UUCP (Fred Fierling) writes:
>We recently replaced an ailing IBM disk controller with a Western Digital
>WD1006 in an IBM AT running Xenix 2.2.1 and used a program from
>comp.binaries.ibm.pc called "iau" to change the interleave.  To our surprise
>the program, which performs interleave adjustments non-destructively on DOS
>disks, trashed the Xenix filesystem on the disk.
>
>I don't understand why this would happen.  Seems to me the order of the 
>sectors in a track is of little concern to operating systems.  Can anybody
>explain why this wouldn't work?

Sounds like the utility is a little too smart for it's own good, and tried
to do something with what it thought was a MSDOS system disk...

>Also, anybody know of a utility that non-destructively changes disk interleave
>and runs under Xenix?

We have used Speedstor (Storage Dimensions' product) to change interleave on
Xenix disks and have not yet had a problem.  You do need to be somewhat
careful; we always set up the disk as having one less cylinder than it
really does have (in case we need to run diags on it in the future); I do
not believe this is significant.

For RLL disks, you need to say "/secs:26" on the Speedstor command line.

This utility has been quite helpful for refreshing the format on a few disk
drives that we have here without having to dump and reload the data.  I
would back it up first anyway (we always do), but we've never needed the
backup yet :-)

--
Karl Denninger (karl@ddsw1.MCS.COM, !ddsw1!karl)
Public Access Data Line: [+1 312 566-8911], Voice: [+1 312 566-8910]
Macro Computer Solutions, Inc.		"Quality Solutions at a Fair Price"