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Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!simtel!lll-winken.llnl.gov!hookup!news.uoregon.edu!vixen.cso.uiuc.edu!uchinews!ncar!noao!math.arizona.edu!news.Arizona.EDU!canopus!tom From: tom@canopus.as.arizona.edu (Thomas J. Trebisky) Newsgroups: comp.unix.bsd.netbsd.misc Subject: Re: Translated geometry Date: 13 Aug 1995 03:41:00 GMT Organization: Steward Observatory, Tucson, Arizona Lines: 50 Message-ID: <40js8c$gjs@news.ccit.arizona.edu> References: <Pine.SOL.3.91.950810081116.19831A-100000@ritz> NNTP-Posting-Host: canopus.as.arizona.edu Cc: In article <Pine.SOL.3.91.950810081116.19831A-100000@ritz>, Bill R. Fink <wrf1@cec.wustl.edu> wrote: >I have a 1.08GB HD where the BIOS setup is reporting one geometry >and PFDISK is reporting another. When I go to partition my HD, I want >to have a 700MB DOS partition and a 300MB netBSD parition. I suppose that >the geometry from PFDISK is showing is translated. What kind of disk? IDE? >When I went to install netBSD, I did the following: > PFDISK the partition using the translated values > Changed the geometry setting (within PFDISK) and wrote the > physical and logical values down (as reported by PFDISK) > Booted with the netBSD floppy ans proceeded with the install > netBSD reported the dsk with the smae values as the BIOS did > I used the netBSD values and set the partition as reported by > PFDISK (the physical values) > >When finished with the install...you guessed it...no netbsd AND no more DOS! > >Question: Should I be consistant and use the translated values? > Wh is there geometry translation (too many cylinders for DOS?) > What should I do to have DOS report a smaller C: drive once I > take away 300MB with PFDISK? First off, any time you repartition (i.e. run pfdisk or fdisk), you are going to loose everything on the disk. This is true just in the DOS world. So, to get DOS to use a smaller partition, do [P]FDISK, FORMAT c:/s (or whatever), and there you are, ready to reload DOS, but you might wait on that till you get the NetBSD stuff going. You are probably going to want to load OS-BS or some other boot selector to make your life reasonable too right off the bat. This disk geometry business is kind of a mess when trying to keep the BIOS, DOS, and NetBSD all playing together. The BIOS and I presume OS-BS use the CMOS ram geometry values to get things booted. NetBSD never looks at the CMOS geometry as far as I know. It relies upon the info in its own label, and it is pretty helpful if it is consistent with what the BIOS and the partition table are using. So yep, you need to use a consistent set of parameters (whatever that means for you.). And yes, the reason for translation is brain damage in the BIOS code which needs to root around on the disk to get you booted. I think the BIOS is unable to deal with more than 1024 cylinders (for no particular reason that occurs to me other than that being the limit in the old WD1010 controller chip that almost all PC's used to use back in the MFM days.) -- Tom Trebisky Steward Observatory ttrebisky@as.arizona.edu University of Arizona (602) 621-5135 Tucson, Arizona 85721