[CentOS] strange disk space calculation ext4 df and du

[Jonathan Billings]

On Mon, Nov 03, 2014 at 04:53:05PM +0100, Götz Reinicke - IT Koordinator wrote:
> in one server I do have a SSD raid 1 size 219GB.
> 
> df shows 9.4 GB free, 198GB used.
> 
> If I do "du -sch * | sort -h -r" on /, I just have close to 3.5GB used ....
> 
> Any hints, what's eating up the space?

Deleted files (check out the output of 'lsof' and look for deleted
files)?  This happens a lot when your log rotation system rotates a
log but the daemon logging to it isn't restarted or told to use the
new log files.

Also, you could have sparse files (read the man page for 'du' under
--apparent-size) that appear to be using more space than 'du' normally
reports. 

-- 
Jonathan Billings <billings at negate.org>