Subject: Re: Disklabel troubles
To: H. Jared Agnew <jagnew@vtaix.cc.vt.edu>
From: Michael L. Hitch <mhitch@lightning.oscs.montana.edu>
List: port-pmax
Date: 10/30/1996 16:01:10
On Oct 29, 11:04pm, "H. Jared Agnew" wrote:
>   I'm having a bit of trouble labeling my rz25.  The disktab that comes with
> netbsd doesn't seem to work.  I have my pmax booting diskless of of a FreeBSD
> box, but I can not get the pmax to disklabel the rz25.  This is what
...
> total sectors: 832527
...
> rz25|RZ25|DEC RZ25 Winchester:\
>         :dt=SCSI:ty=winchester:ns#62:nt#9:nc#1476:\
                                 ^^^^^^^^^^^^^^^^^^
  62 * 9 * 1476 = 823608

>         :pc#832527:oc#0:bc#8192:fc#1024:\

  And 823608 < 832527, which will generate the errors.

> and here are the errors.
> 
> disklabel: partition c: partition extends past end of unit
> disklabel: partition f: partition extends past end of unit
> disklabel: partition g: partition extends past end of unit

  I think this is probably because the RZ25 has a variable number of sectors
per track and the value 62 is a rough average.  The number of cylinders
specified is probably the actual number of cylinders on the disk, but the
62 sectors/track will give you a total sector count less than the actual
total count.  This is probably "safe", as you wouldn't be trying to use
any non-existant sectors.  However, disklabel checks the partition end
and complains if it extends past what the cylinder/head/sector values
specify.

  I have an RZ25 that has the number of cylinders set to 1492, which results
in a "size" of 832536 blocks, which makes disklabel happy.

Michael

-- 
Michael L. Hitch			INTERNET:  mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA