Im running a CentOS 7 box that has a very simple setup. It has a few NFS drives mounted on it and it runs a script that pulls in a list of filenames from some image processor servers. It uses very small amount of hd space since its just basically keeping a log of the files that are being transferred. Just recently it started eating up a ton of space and maxed the drive and broke the jobs. I used du and find commands to locate the larger files and then deleted roughly 3.5GB (total drive on the server is 20GB). I noticed that some of the deletions did not give me space back so I checked with lsof and ps to see if any file was still in use -- nothing. The files I removed were .txt files that were old transaction logs from a few years ago, so I didn't see how they could still be in use.  Right now the drive got maxed out again but I can't find where the space is. DU doesn't locate any big directories, find isn't showing me anything either when I try to look for files changed within the past day or something. Where could the space go? Any reason why DU can't find it? Am I missing some other tool that can better scan the hard drive? Hm... like a CLI graphical tool like WinDirStat or DiskInventoryX or something like that? I ended up adding HD space to the server to resolve the issues so we could process again, but im slowly seeing the space increase without seeing any changes in directory sizes on DU.   Thanks for any ideas that ya'll may have. 
Drive fills up after removal but unable to find the new files that are eating the space
filesystems;disk usage