jim@jagmac2.gsfc.nasa.gov (Jim Jagielski) (07/05/90)
The characteristics of a disk drive's geometry needs to be included in A/UX
2.0 /etc/disktab file. There are two ways of getting this information: either
from SCSI Evaluator OR LaCie SilverLining.
My trouble is that both return DIFFERENT values for the number of cylinders
for all my hard disks. Which should I believe? For example, for my Quantum
80 (the newer 3 1/2 inch) SCSI Eval. returns 834 cylnders, whereas SL returns
837 (and 6 heads, 32 sectors/track)... (SL is 5.24/09 and SCSI Eval is
both 1.00 and 1.03)
????????
--
=======================================================================
#include <std/disclaimer.h>
=:^)
Jim Jagielski NASA/GSFC, Code 711.1
jim@jagmac2.gsfc.nasa.gov Greenbelt, MD 20771
"Kilimanjaro is a pretty tricky climb. Most of it's up, until you reach
the very, very top, and then it tends to slope away rather sharply."urlichs@smurf.sub.org (Matthias Urlichs) (07/07/90)
In comp.unix.aux, article <2698@dftsrv.gsfc.nasa.gov>,
jim@jagmac2.gsfc.nasa.gov (Jim Jagielski) writes:
< The characteristics of a disk drive's geometry needs to be included in A/UX
< 2.0 /etc/disktab file.
Side question: Are these values used for anything, or are they just there for
performance reasons (mkfs for a BSD file system)?
Why can't these utilities pretty please _ask_ the SCSI drive, instead of
pestering us poor clueless users with maintaining that stuff?
And what, if anything, are we to do with drives which have a variable number
of sectors (depending on the track)?
< There are two ways of getting this information: either
< from SCSI Evaluator OR LaCie SilverLining.
<
< My trouble is that both return DIFFERENT values for the number of cylinders
< for all my hard disks. Which should I believe? For example, for my Quantum
< 80 (the newer 3 1/2 inch) SCSI Eval. returns 834 cylnders, whereas SL returns
< 837 (and 6 heads, 32 sectors/track)... (SL is 5.24/09 and SCSI Eval is
< both 1.00 and 1.03)
<
It seems that SilverLining includes the spare sectors.
Since the SCSI drive doesn't make these available to ordinary mortals (or
ordinary file systems), you probably should believe SCSI Evaluator.
Disclaimer: Anything I said could be wrong.
--
Matthias Urlichs -- urlichs@smurf.sub.org -- urlichs@smurf.ira.uka.de
Humboldtstrasse 7 - 7500 Karlsruhe 1 - FRG -- +49+721+621127(Voice)/621227(PEP)cander@unisoft.UUCP (Charles Anderson) (07/10/90)
From article <2698@dftsrv.gsfc.nasa.gov>, by jim@jagmac2.gsfc.nasa.gov (Jim Jagielski): > The characteristics of a disk drive's geometry needs to be included in A/UX > 2.0 /etc/disktab file. There are two ways of getting this information: either > from SCSI Evaluator OR LaCie SilverLining. > > My trouble is that both return DIFFERENT values for the number of cylinders > for all my hard disks. Which should I believe? For example, for my Quantum > 80 (the newer 3 1/2 inch) SCSI Eval. returns 834 cylnders, whereas SL returns > 837 (and 6 heads, 32 sectors/track)... (SL is 5.24/09 and SCSI Eval is > both 1.00 and 1.03) Actually the best way would be to read the drive manual or call the drive manufacturer (I beleive Quantum's number is 408/432-1100, or call Milpitas information). Unfortunately my Pro Series drive manual is at home. Since you seem to have the cylinder dimensions (6x32), you could cheat and use dd on slice 31 (whole disk) with bs=192. This will take a while, but it should return the cylinder count. -- Charles. {sun, ucbvax, pyramid, uunet}!unisoft!cander "Unix is the Winchester Mystery House of software design." -- me