Cylinder issue

[nani]

Hi Have this layout

Device Boot    Start       End    Blocks   Id  System
/dev/sda1   *         1        13    104391   83  Linux
/dev/sda2            14     12761 102398310   83  Linux
*/dev/sda3         12762     15312  20490907+  83  Linux
/dev/sda4         30543     35642  40965750    f  Win95 Ext'd (LBA)*
/dev/sda5         30543     33092  20482843+  83  Linux
/dev/sda6         33093     35642  20482843+  83  Linux
[root at ktwmbak2 1]#

If you could see that /dev/sda3 is ended up with 15312 and /dev/sda4 has
started with 30543

If I wanted to create a new partition starting with cylinder of 15313 it is
not allowing me

[root at ktwmbak2 1]# fdisk /dev/sda

The number of cylinders for this disk is set to 35642.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): n
No free sectors available

My Disk is of Size 287GB

and DF -h output is

[root at ktwmbak2 root]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda3              20G   13G  5.9G  68% /
/dev/sda1              99M   36M   58M  39% /boot
/dev/sda2              97G   43G   50G  47% /opt/oracle
/dev/sda6              20G   33M   19G   1% /opt/oracle/archlog
/dev/sda5              20G  5.9G   13G  32% /opt/redprarie
none                  4.0G     0  4.0G   0% /dev/shm
[root at ktwmbak2 root]#

Please suggest on this missing cylinders

Thanks and Regards,
Srinath
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