XK0-006 System Management Practice Question
Which command displays the amount of disk space used and available on mounted filesystems in a human-readable format (e.g., GB, MB)?
⚠ Common exam trap
Candidates often confuse `du -h` (which shows directory-level usage) with `df -h` (which shows filesystem-level capacity), leading them to select option C when the question explicitly asks for disk space on mounted filesystems.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
df -h
The `df -h` command displays disk space usage for all mounted filesystems, with the `-h` flag converting raw block counts into human-readable units like GB or MB. This is the standard Linux utility for reporting filesystem capacity, usage, and available space, making it the correct choice for the question.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
df -h
Why this is correct
The -h flag converts df's default 1K-block output into human-readable units such as GB and MB, while df itself reports used and available space per mounted filesystem. This satisfies the requirement for human-readable capacity figures.
- ✗
lsblk
Why it's wrong here
lsblk enumerates block devices and their mountpoints, showing device and partition sizes rather than filesystem-level used and available space. It is tempting because it displays storage layout with human-readable sizes, but it does not report free space on mounted filesystems, which df -h provides.
- ✗
du -h
Why it's wrong here
du reports per-directory disk usage by walking file trees, not filesystem capacity or free space on mounted volumes. It is tempting because the -h flag does produce human-readable sizes, but that applies to directory consumption; df -h is the command that queries mounted filesystems for used and available space.
- ✗
fdisk -l
Why it's wrong here
fdisk -l lists partition tables, disk geometry and partition sizes, not the used and available space on mounted filesystems. It is tempting because it reports disk-related capacity figures, but it reads partition metadata rather than mounted filesystem statistics, so df -h is required for the stated output.
Go deeper
Related to this question
Learn chapter
Navigating the Filesystem
Key term
Linux
Linux is an open-source operating system that manages computer hardware and software, widely used in servers, desktops, and embedded systems.
Key term
Utility
Utility, in IT service management, is the measure of a service's functionality that ensures it is fit for purpose by meeting the specific needs of the customer.
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JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This XK0-006 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the XK0-006 exam.