The answer is that the command displays help for syslog messages that include 'error'. This is accomplished by using the pipe (|) with the match filter, which acts as a grep-like function in the Junos CLI, scanning the output of 'show log messages' and returning only lines containing the string 'error'. On the JNCIA-Junos exam, this tests your understanding of operational mode filtering and the specific behavior of the 'show log messages' command, which is a core syslog viewing tool. A common trap is assuming the match filter performs a whole-word search or that it modifies the log file itself—it does not; it simply filters the displayed output. Remember the memory tip: "Match is a magnifying glass, not a scalpel"—it highlights relevant lines without altering the underlying log data.
JNCIA-JUNOS User Interfaces Practice Question
This JNCIA-JUNOS practice question tests your understanding of user interfaces. Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. 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.
Exhibit
user@router> help syslog messages | match error
KERNEL_ERROR Kernel error messages
USER_ERROR User-level error messages
DAEMON_ERROR Daemon error messages
Refer to the exhibit. What does this command accomplish?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Displays help for syslog messages that include 'error'.
The command 'show log messages | match error' uses a pipe to filter the output of the 'show log messages' command, displaying only lines that contain the string 'error'. However, the question asks what the command accomplishes, and the correct answer is A because the '| match' filter is essentially a help mechanism to find relevant syslog messages, and the exhibit likely shows 'show log messages | match error' which is a common way to display help for syslog messages that include 'error'. The command does not display all syslog messages (B), does not display only messages containing the word 'error' as a whole word (C), and does not display an error log file (D).
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.
✓
Displays help for syslog messages that include 'error'.
Why this is correct
The 'help syslog messages' command provides descriptions of syslog message types; the pipe filters to those with 'error' in the description.
Related concept
Read the scenario before looking for a memorised answer.
✗
Displays all syslog messages.
Why it's wrong here
Only shows those with 'error' in the help text.
✗
Displays syslog messages containing the word 'error'.
Why it's wrong here
This shows help information, not actual syslog messages.
✗
Displays the error log file.
Why it's wrong here
The command is 'help syslog messages', not 'show log'.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume 'match error' performs a whole-word search or that there is a dedicated error log file, when in reality it is a substring match on the default messages log file.
Trap categories for this question
Command / output trap
Only shows those with 'error' in the help text.
Detailed technical explanation
How to think about this question
In Junos, the 'show log' command reads the /var/log/messages file by default, and the pipe to 'match' uses a regular expression (grep) to filter lines. The 'match' operator is case-sensitive by default and matches any occurrence of the string, not whole words. This is useful for quickly isolating specific events in a large log file, such as when troubleshooting interface flaps or routing protocol errors, where searching for 'error' can reveal critical syslog entries without needing to parse the entire log.
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 practitioner preparing for the JNCIA-JUNOS 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
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
User Interfaces — This question tests User Interfaces — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Displays help for syslog messages that include 'error'. — The command 'show log messages | match error' uses a pipe to filter the output of the 'show log messages' command, displaying only lines that contain the string 'error'. However, the question asks what the command accomplishes, and the correct answer is A because the '| match' filter is essentially a help mechanism to find relevant syslog messages, and the exhibit likely shows 'show log messages | match error' which is a common way to display help for syslog messages that include 'error'. The command does not display all syslog messages (B), does not display only messages containing the word 'error' as a whole word (C), and does not display an error log file (D).
What should I do if I get this JNCIA-JUNOS 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 JNCIA-JUNOS practice question is part of Courseiva's free Juniper Networks 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 JNCIA-JUNOS 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.