This LPIC-1 practice question tests your understanding of devices, filesystems and fhs. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A server has a partition /dev/sda2 that is almost full. The admin suspects a large file has been deleted but is still held open by a process. Which command can identify such a file?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "which command"
Why it matters: Tests specific CLI syntax. Recall the exact command and its required context — near-synonyms and partial matches are common distractors.
du -sh /
Why wrong: Shows disk usage but does not list open files.
find / -size +100M
Why wrong: Finds large files but cannot detect deleted open files.
lsof | grep deleted
Shows open files marked as deleted.
df -h
Why wrong: Shows filesystem usage but not individual files.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
lsof | grep deleted
The `lsof` command lists open files and their associated processes. When a file is deleted but still held open by a process, `lsof` shows the filename with a '(deleted)' marker in its output. Piping through `grep deleted` filters for exactly those entries, allowing the admin to identify the file and the process keeping it alive, which is the precise scenario described.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
du -sh /
Why it's wrong here
Shows disk usage but does not list open files.
find / -size +100M
Why it's wrong here
Finds large files but cannot detect deleted open files.
lsof | grep deleted
Why this is correct
Shows open files marked as deleted.
Clue confirmation
The clue word "which command" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
df -h
Why it's wrong here
Shows filesystem usage but not individual files.
Common exam traps
The trap here is that candidates often choose `df -h` or `du` because they show disk usage, but they fail to realize that deleted-but-open files are invisible to those tools, while `lsof` directly reveals the hidden space consumption.
Trap categories for this question
Command / output trap
Shows disk usage but does not list open files.
Detailed technical explanation
Under the hood, when a file is deleted while a process holds an open file descriptor, the kernel does not free the inode or data blocks until all references (including the file descriptor) are closed. The `lsof` command reads kernel data structures (via /proc on Linux) to list open file descriptors; for unlinked files, it appends '(deleted)' to the filename. This behavior is critical in production environments where a runaway log file or temporary file can fill a partition even after being 'removed' by the application.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the LPIC-1 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Devices, Filesystems and FHS — study guide chapter
Learn the concepts, then practise the questions
Devices, Filesystems and FHS practice questions
Targeted practice on this topic area only
All LPIC-1 questions
522 questions across all exam domains
Linux Professional Institute Certification Level 1 LPIC-1 study guide
Full concept coverage aligned to exam objectives
LPIC-1 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise LPIC-1 questions linked to GNU and Unix Commands.
Practise LPIC-1 questions linked to Devices, Filesystems and FHS.
Practise LPIC-1 questions linked to Linux Installation and Package Management.
Practise LPIC-1 questions linked to Essential System Services and Networking.
Practise LPIC-1 questions linked to Administrative Tasks.
Practise LPIC-1 questions linked to Shells, Scripting and Data Management.
Practise LPIC-1 questions linked to System Architecture.
Practise LPIC-1 questions linked to LPIC-1 fundamentals.
Practise LPIC-1 questions linked to LPIC-1 scenario.
Practise LPIC-1 questions linked to LPIC-1 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Devices, Filesystems and FHS — This question tests Devices, Filesystems and FHS — Read the scenario before looking for a memorised answer..
The correct answer is: lsof | grep deleted — The `lsof` command lists open files and their associated processes. When a file is deleted but still held open by a process, `lsof` shows the filename with a '(deleted)' marker in its output. Piping through `grep deleted` filters for exactly those entries, allowing the admin to identify the file and the process keeping it alive, which is the precise scenario described.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Yes — watch for: "which command". Tests specific CLI syntax. Recall the exact command and its required context — near-synonyms and partial matches are common distractors.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 25, 2026
This LPIC-1 practice question is part of Courseiva's free LPI 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 LPIC-1 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.