Disk geometry, 5.3b7 install

freebsd at dreamchaser.org freebsd at dreamchaser.org
Thu Oct 14 01:03:24 PDT 2004


Subhro wrote:

>>When I boot off a CD (image created from downloaded iso image),
>>start the install, and go to allocate the freebsd slice, it reports
>>  155061/16/63  ad4
>>and says the geometry is invalid
> 
> What does the sticker on top of the drive say about its geometry. I
> would like to explicitly instruct fdisk to use the Geometry on the
> sticker but only if fdisk or anyone else complains during the install.

There is nothing about geometry on the drive itself.
The official specs from Seagate say it reports a default logical
geometry of 16383/16/63, but that only covers 8G...
There is no other mention of geometry in the specs;
it simply says that using LBA the sectors are addressed 0...n-1

>>If I go ahead and attempt to partition, I see
>>Geometry ad4 9729 cylinders/255 heads/63 sectors = 156296385 sectors
>>                                                   (76316MB)
>>  Offset   Size(St)    End      Name  PType  Desc      SubType  Flags
>>       0         63         62   --    12   unused         0
>>      63   16386237   16386299  ad4s1   4   NTFS/HPFS/QNX  7
>>16386300  139915188  156301487   --    12   unused         0
>>
> 
> 
> This one is fine. Whats the problem? You can just make up the slice
> from the unsed free space starting from offset 16386300.

The only problem is that the geometry was reported as bad by
sysinstall, and implied I needed to change it.
Yet the partition step appears to have changed it already, or is
assuming it will be changed.
I don't understand what the situation is:
   sysinstall reported geometry as 155061/16/63 and said it was bad
   then partitioning assumes it will be  9729/255/63
Do I actually have to run pfdisk to change it from 155061/16/63 to
9729/255/63?

One more question:

The installation notes say the root partition must be below cylinder
1024.  If I want a largish (8G) partition for windows, how do I
accomplish this?  Do I have to make 4 partitions, a small one for
booting windows, a small one for freebsd's root, and then a larger
one for the rest of windows and another larger one for the rest of
freebsd?
e.g.
      cyl    partition    use
     1- 511      1        windows boot
   512-1023      2        freebsd /
  1024-1500      3        windows additional stuff
  1501-9729      4        freebsd filesystems other than /

Thanks,

Gary


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