gentoolinux evert # df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda4             121G  109G  5.4G  96% /
udev                  506M  268K  506M   1% /dev
/dev/sda2              38M  5.2M   31M  15% /boot
none                  506M     0  506M   0% /dev/shm
/dev/sda1             157G   61G   96G  39% /mnt/data

gentoolinux evert # umount /mnt/data

gentoolinux evert # df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda4             121G  109G  5.4G  96% /
udev                  506M  268K  506M   1% /dev
/dev/sda2              38M  5.2M   31M  15% /boot
none                  506M     0  506M   0% /dev/shm
gentoolinux evert # fdisk /dev/sda1

The number of cylinders for this disk is set to 20397.
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): m
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty DOS partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty Sun disklabel
   t   change a partition's system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)

Command (m for help): p

Disk /dev/sda1: 167.7 GB, 167779229184 bytes
255 heads, 63 sectors/track, 20397 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

This doesn't look like a partition table
Probably you selected the wrong device.

     Device Boot      Start         End      Blocks   Id  System
/dev/sda1p1   ?       13578      119522   850995205   72  Unknown
Partition 1 does not end on cylinder boundary.
/dev/sda1p2   ?       45382       79243   271987362   74  Unknown
Partition 2 does not end on cylinder boundary.
/dev/sda1p3   ?       10499       10499           0   65  Novell Netware 386
Partition 3 does not end on cylinder boundary.
/dev/sda1p4          167628      167631       25817+   0  Empty
Partition 4 does not end on cylinder boundary.

Partition table entries are not in disk order

Command (m for help):