The answer is to run `ss -tlnp | grep :4444` to identify the process ID (PID), then use `kill` to terminate the unauthorized service. This is correct because `ss -tlnp` displays all TCP listening sockets with numeric ports and the associated PID, and piping to `grep :4444` isolates the offending service. Since the service is not managed by systemd, `systemctl` commands cannot control it, making `kill` the only viable method to stop it. On the CompTIA Linux+ XK0-005 exam, this scenario tests your ability to audit network services and handle rogue processes outside systemd’s control—a common trap is reaching for `systemctl stop` when the service lacks a unit file. Remember the mnemonic: “SS to see, kill to free.”
XK0-005 Troubleshooting Practice Question
This XK0-005 practice question tests your understanding of troubleshooting. 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.
During a security audit, a Linux administrator finds that an unauthorized service is listening on TCP port 4444. The service is not managed by systemd. Which of the following commands should the administrator use to identify the process and disable it?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Run 'ss -tlnp | grep :4444' to find the PID, then use 'kill' to terminate the process.
Option A is correct because 'ss -tlnp' lists TCP listening sockets with numeric addresses and the associated process PID. Piping the output through 'grep :4444' isolates the unauthorized service, and the PID can then be used with 'kill' to terminate the process. Since the service is not managed by systemd, systemctl commands are irrelevant, making 'kill' the appropriate method to stop the process.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
Run 'ss -tlnp | grep :4444' to find the PID, then use 'kill' to terminate the process.
Why this is correct
ss -tlnp shows listening sockets with PIDs; kill can then stop the process.
Related concept
Read the scenario before looking for a memorised answer.
✗
Run 'fuser 4444/tcp' to find the PID and then use 'systemctl stop' to stop the service.
Why it's wrong here
fuser can find the PID, but systemctl cannot stop a non-systemd service.
✗
Run 'lsof -i :4444' to find the PID, then use 'systemctl disable' to disable the service.
Why it's wrong here
lsof finds the PID but systemctl disable only applies to systemd services.
✗
Run 'systemctl status' to find the service name, then use 'systemctl stop' to stop it.
Why it's wrong here
systemctl cannot show or manage non-systemd services.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates assume all services are managed by systemd and reach for 'systemctl stop' or 'systemctl disable', but the question explicitly states the service is not managed by systemd, so only process-level commands like 'kill' are valid.
Trap categories for this question
Command / output trap
systemctl cannot show or manage non-systemd services.
Detailed technical explanation
How to think about this question
The 'ss' command reads socket information from the /proc/net/tcp and /proc/net/tcp6 files, providing a snapshot of current TCP connections and listening sockets. The '-p' flag queries /proc/<PID>/fd to associate each socket with its owning process. In contrast, 'lsof' iterates over all open file descriptors in /proc, which can be slower on systems with many processes. A real-world scenario is a penetration test finding a reverse shell on port 4444 (commonly used by Metasploit), where the attacker's process is not a systemd service, so only 'kill' or 'kill -9' can terminate it.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
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.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this XK0-005 question in full detail.
Troubleshooting — This question tests Troubleshooting — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Run 'ss -tlnp | grep :4444' to find the PID, then use 'kill' to terminate the process. — Option A is correct because 'ss -tlnp' lists TCP listening sockets with numeric addresses and the associated process PID. Piping the output through 'grep :4444' isolates the unauthorized service, and the PID can then be used with 'kill' to terminate the process. Since the service is not managed by systemd, systemctl commands are irrelevant, making 'kill' the appropriate method to stop the process.
What should I do if I get this XK0-005 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
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 →
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.
This XK0-005 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 XK0-005 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.