For us it's either use a 3rd-party software like use TreeSize, or put a share on a qtree and use tracking quota so that the filer reports space usage on each qtree. DFM will also report space used in qtrees. If a share is already in a directory and not a qtree under a volume then we use a 3rd party software. NetApp Host Agent might give you this information. I never used it so I'm not sure what it does, but it seemed like it might do this.