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From: z@rocksvax.UUCP (Jim Ziobro)
Newsgroups: mod.computers.vax
Subject: coexistence of ultrix and vms
Message-ID: <8605280020.AA08242@rocksvax.UUCP>
Date: Tue, 27-May-86 20:20:17 EDT
Article-I.D.: rocksvax.8605280020.AA08242
Posted: Tue May 27 20:20:17 1986
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Another way to allow VMS and Unix to coexist on a single disk is by
modifying the VMS device driver to think that the drive is shorter than
it really is.  All VMS utilities are supposed to query the disk driver
as to its geometry.

We did this on a RP07 once.  For the most part it worked except it
seemed that VMS was writing on the Unix partition randomly anyways.  If
you make the VMS partition 600 cylinders you can boot unix without
modifying the Unix boot floppy by booting the 'g' partition.  Perhaps
some utilties in VMS ignore the values in the device driver.  BTW, this
was back with VMS2. and 4.1BSD.

//Z\\
James M. Ziobro
Ziobro.Henr@Xerox.COM
{rochester,amd,sunybcs,ihnp4}!rocksvax!z
Ziobro:henr801g:xerox