The df -h on the /var is showing the 80GB used size but du -ksh /var is showing 687MB of the total used size of this directory;The total size of the /var partition is 89GB. I am confusing at this point ,also i have gone through the each directories and files size and found everything is normal size ,no files size is above 1GB in the /var directory, but the df -h confuses me and noticed there 80GB used on the /var partition.

kernel version : vmlinuz-
Os version : SUSE Linux Enterprise server 10 sp1

Is this bugs or filesystem for the /var corrupted or hard/soft link on the /var ? should i upgraded from the current version SLES 10 sp1 to higher version? I appreciate your suggestion,recommendation and update.