LFCS Storage Management Practice Question
A company's backup script fails with an error indicating 'no space left on device' on an NFS mount. The administrator checks 'df -h' on the NFS client and sees the mount is at 90% usage. However, the NFS server shows the exported filesystem is only 50% full. What is the most likely cause?
⚠ Common exam trap
Watch out — candidates often assume 'no space left on device' always refers to the remote filesystem, overlooking that the local mount point directory resides on a potentially full local filesystem.
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
✓
The mount point on the client (e.g., /mnt/nfs) is on a local filesystem that is full, preventing writes to the NFS mount.
The NFS mount point on the client (e.g., /mnt/nfs) is itself a directory within a local filesystem. When the local filesystem is full, the kernel cannot create or update the mount point's directory entry, causing writes to the NFS share to fail with 'no space left on device' even though the remote filesystem has free space. This is a classic client-side vs. server-side space confusion.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The 'df' command is caching old data; run 'sync' and then 'df' again.
Why it's wrong here
Caching is possible but not typical cause.
- ✓
The mount point on the client (e.g., /mnt/nfs) is on a local filesystem that is full, preventing writes to the NFS mount.
Why this is correct
When the mount point directory itself is on a full filesystem, writes to that mount point fail.
- ✗
The NFS server is overloaded and not responding in time.
Why it's wrong here
Would cause timeout, not 'no space left on device'.
- ✗
The NFS export has a quota limit that is lower than the actual filesystem capacity.
Why it's wrong here
Quota would produce a different error.
Go deeper
Related to this question
About these practice questions
Courseiva writes every LFCS question from scratch — 507 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This LFCS practice question is part of Courseiva's free Linux Foundation 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 LFCS exam.