The command quota -v does not work because rpc.rquotad under Ubuntu 15.04 segfaults right away. I do not yet know what is causing this but it seems to be fairly unique to us because I’ve Google’d and DuckDuckGo’d and found nada.
It might be that it isn’t working right with RAID devices, or I’ve got something wrong in the fstab or maybe it doesn’t like the i7-7400k CPU (new CPU only out about a month), who knows. Initially quota -v also core dumped on the server but upgrading the kernel from 3.19.0 to 4.2.3 resolved this so at least the command works on the server.
If you believe you are running up against your quota, du -s ~ will at least give you an approximation. If it doesn’t give you enough e-mail support or create a ticket and I’ll look it up manually and e-mail the results.
This is not to say that I’ve given up, but it is a difficult problem. If anyone knows where to obtain source for an older version of rpc.rquotad, please let me know.