Quick Answer
The answer is to use `systemctl disable myapp.service` to permanently prevent a systemd service from starting at boot, but this must be preceded by `systemctl stop myapp.service` to halt the currently running instance. The `disable` command removes the symbolic links that trigger the service during boot, while `stop` ensures the process is terminated immediately, avoiding an inconsistent state where a disabled service remains active. On the LFCS exam, this tests your understanding of systemd’s boot target dependencies and the distinction between runtime control and persistent configuration. A common trap is assuming `disable` alone suffices; the exam expects you to recognize that stopping the service first is a necessary step for a clean, permanent disable. Remember the mnemonic “Stop before you drop the link” — stop the service, then disable the boot link.
This LFCS practice question tests your understanding of operation of running systems. 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.
Which THREE steps are necessary to permanently disable a systemd service from starting at boot?
systemctl stop myapp.service
Stops the currently running service.
systemctl mask myapp.service
Masks the service, preventing it from being started manually or by dependencies.
systemctl reset-failed myapp.service
Why wrong: Resets the 'failed' state, irrelevant to disabling.
systemctl disable myapp.service
Prevents the service from starting at boot.
systemctl daemon-reload
Why wrong: Reloads systemd configuration, not needed for disabling.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
systemctl stop myapp.service
Option A is correct because `systemctl stop` immediately terminates the service process, which is necessary to ensure the service is not currently running before disabling it from future boots. While stopping alone does not prevent the service from starting at boot, it is a required step in the process of permanently disabling a service, as you must stop the current instance before disabling it to avoid an inconsistent state.
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.
systemctl stop myapp.service
Why this is correct
Stops the currently running service.
Related concept
Read the scenario before looking for a memorised answer.
systemctl mask myapp.service
Why this is correct
Masks the service, preventing it from being started manually or by dependencies.
Related concept
Read the scenario before looking for a memorised answer.
systemctl reset-failed myapp.service
Why it's wrong here
Resets the 'failed' state, irrelevant to disabling.
systemctl disable myapp.service
Why this is correct
Prevents the service from starting at boot.
Related concept
Read the scenario before looking for a memorised answer.
systemctl daemon-reload
Why it's wrong here
Reloads systemd configuration, not needed for disabling.
Common exam traps
The trap here is that candidates often think `systemctl disable` alone is sufficient to prevent a service from starting at boot, but they forget that the service may still be running currently, and without stopping it first, the disable command only affects future boots, not the current session.
Detailed technical explanation
When you run `systemctl disable`, systemd removes the symlinks from the `/etc/systemd/system/multi-user.target.wants/` (or similar target directories) that cause the service to start automatically. `systemctl mask` goes further by symlinking the unit file to `/dev/null`, making it impossible to start even manually until unmasked. The combination of stop, disable, and mask ensures the service is not running, will not start on boot, and cannot be started accidentally.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Operation of Running Systems — study guide chapter
Learn the concepts, then practise the questions
Operation of Running Systems practice questions
Targeted practice on this topic area only
All LFCS questions
513 questions across all exam domains
Linux Foundation Certified System Administrator LFCS study guide
Full concept coverage aligned to exam objectives
LFCS 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 LFCS questions linked to User and Group Management.
Practise LFCS questions linked to Operation of Running Systems.
Practise LFCS questions linked to Essential Commands.
Practise LFCS questions linked to Networking.
Practise LFCS questions linked to Service Configuration.
Practise LFCS questions linked to Storage Management.
Practise LFCS questions linked to LFCS fundamentals.
Practise LFCS questions linked to LFCS scenario.
Practise LFCS questions linked to LFCS troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Operation of Running Systems — This question tests Operation of Running Systems — Read the scenario before looking for a memorised answer..
The correct answer is: systemctl stop myapp.service — Option A is correct because `systemctl stop` immediately terminates the service process, which is necessary to ensure the service is not currently running before disabling it from future boots. While stopping alone does not prevent the service from starting at boot, it is a required step in the process of permanently disabling a service, as you must stop the current instance before disabling it to avoid an inconsistent state.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Keep practising
Last reviewed: Jun 11, 2026
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.
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.