This piece is taken from a broader article I wrote discussing quota usage and some of the unsung dangers that can occur when disk space runs low. The original covers both Linux Plesk and cPanel servers, those particular parts of the original source will be published as their own articles.  As always, you can find all my currently published articles with other parties on the External Publications page here on cpguy.com.

Article Name: How to Use Disk Quota in Dedicated Linux Servers
Published: 2018-05-17
Publisher: Liquid Web Knowledge Base
Author: Jason M Potter – The cPanel Guy