Missing hard drive space. df and du can't agree

[tsan]

Hi I have been searching for the 'lost' hard drive space on the root partition of one of my servers.
6.2-RELEASE-p5 FreeBSD 6.2-RELEASE-p5
When I peform a df -h for the root partition I get this
gol-goroth# df -h
Filesystem Size Used Avail Capacity Mounted on
/dev/ad0s1a 496M 453M 3.2M 99% /

Using the du -xh / | grep M command I get the output of

1.0M ./etc/rc.d
4.2M ./etc
19M ./boot/kernel
19M ./boot
3.5M ./lib
4.0M ./sbin
33M .

This would indicate that the / partition has 33mb of data on it. What I don't understand is why there is a difference between the 2 commands. When I try and copy data onto the / partition I get an error that it is out of space. I have only included the du output of M as the complete listing results in 33Mb being used.

Is there anything I have potentially missed ?

Any suggestions would be appreciated.

[s0xxx]

You might have symbolic links, try using du -hxL

Or, you have an "open file descriptor(s)" that you have to deal with, see:
http://www.cyberciti.biz/tips/freebs...nt-output.html
http://www.walkernews.net/2007/07/13...ed-disk-space/

[J65nko]

FreeBSD reserves 8 % of the disk space, which only root can fill. This 8% is is not mentioned in the df statistics.

OpenBSD does the same, only there the percentage is 5%.

For more info see the FreeBSD FAQ: http://www.freebsd.org/doc/en_US.ISO....html#DU-VS-DF and http://www.freebsd.org/doc/en_US.ISO...MORE-THAN-FULL