The command "df -h" no show me the size of partition true!

[Alessandro Viana]

 Hi,

 I be the following problem: When I execute the command "df -h" the
 system show me the size from partition /home with 916MB Used. But, when
 I execute "du -h -s" the system show me only 231MB in use in /home.
 I am use Red Hat AS 2.1!

 See you the problem below: (Look /home!)

 [root at server1 root]# df -h
 Filesystem Size Used Avail Use% Mounted on
 /dev/sda2 2.0G 470M 1.4G 25% /
 /dev/sda1 152M 19M 125M 14% /boot
 /dev/sda10 19G 4.0G 13G 23% /data
 /dev/sda6 1.0G 916M 66M 94% /home
 /dev/sda9 4.9G 823M 3.8G 18% /opt
 none 2.0G 0 1.9G 0% /dev/shm
 /dev/sda7 1.0G 87M 895M 9% /tmp
 /dev/sda3 2.0G 946M 975M 50% /usr
 /dev/sda5 2.0G 665M 1.2G 35% /var
 server6:/backup/tomate1
 166G 83G 75G 53% /backup

 [root at server1 root]# du -h -s /home/
 231M /home

    I rebooted the system. The kenel is 2.4.9-e.43enterprise!
 
Can somebody help me?

 Alessandro.