I am sure you guys have seen this a hundred times. I tried looking through groups.google.com for information on this, which I did find, but nothing that really said how to fix the problem. All my findings just basically said how the two programs read size information differently. Here is my situation, all I have done is install the base OS from a cd, then remove certain packages via dpkg (along with deleting some empty dir's and such). I haven't added ANY files to the system or made ANY links to anything. When I run du on each root directory (ie. /boot, /dev, etc), I totaled up the sizes given for each directory, the total OS size is reported as being around 22mb. If I run the df command, I get a total OS size of 55mb. I would understand if the two figures were close to one another, but the df size is more than double that of the du size.
During my readings in groups.google.com, some people said to check what mounts you have because df reports sizes from those also. I have no mounts to anything (my mtab file only contains /dev/hda3 (which is my root partition) and the proc fs). Also I only have 2 partitions, 1 for swap, 1 for all the rest. I have rebooted and checked the sizes again, as well as shutdown completely and check the sizes with no changes.
To make thing even more wierd, I copied the entire root directory structure to another (unused) partition (/dev/hda4), then ran df on /dev/hda4 and it reported the same file size as df on /dev/hda1 (the partition mentioned above that stores all the root directories). Then I deleted all contents off the /dev/hda4 partition and ran df again. This time df said that there was a little over 30mb used on /dev/hda4 EVEN THOUGH I JUST DELETED EVERYTHING ON IT. Those 30mb are the exact difference between what size I get when running df on /dev/hda1 and adding up all the sizes that du reports for each root directory. Can someone PLEASE HELP ME!