Linux Terminal Command: df

The df command is an essential tool in System Information & Hardware. In this tutorial, we will explore what df does, look at everyday examples, and cover advanced options to supercharge your command-line workflow.

Concept & Explanation

The df command displays the total size, used space, available space, and mount points of all active filesystems.

Common Options & Syntax

df [options] [arguments]

Here are the most common flags used with df:

Simple Usage: Basic default commands.
Detailed View: Shows diagnostic information.
Advanced Actions: Can chain parameters for scripting.

1. Interactive Example (Simple)

Here is how most people run the command:

# Example
df -h

What it does: Displays disk usage details in human-readable formats (e.g. GB, MB).

2. Power-User Example (Advanced)

For scripting and advanced diagnostics, use this configuration:

# Advanced
df -lhT -x tmpfs -x devtmpfs

What it does: Filters out temporary filesystems (tmpfs) and displays disk types (-T) for local physical storage only.

⚙️ Warning & Common Pitfalls

[!WARNING] On systems with hung network mounts (like NFS), running df can hang indefinitely. Use df -l to query local filesystems only.

Here are some related posts on cli_tty1 you might want to check out:

du : Estimate file space usage.
free : Display amount of free and used memory in the system.
uname : Print system information.