Viewing disk usage
Keeping an eye on your storage is always important, as no one enjoys getting a call in the middle of the night saying that a server encountered an issue, especially not something that could've been easily avoided, such as a filesystem growing too close to being full. Managing storage on Linux systems is simple once you master the related tools, the most useful of which I'll go over in this section. In particular, we'll look at tools we can use to answer the question "what's using up all the disk space?", which is the most common question that comes up when dealing with disk usage.
First, let's look at the df command.
Using df
The df command is likely always going to be your starting point in situations where you don't already know which volume or mount point is becoming full. When executed, it gives you a high-level overview, so it's not necessarily useful when you want to figure out who or what in particular...