The answer is that the tilde (~) indicates the NTP server is reachable but not the one currently selected for synchronization. This is because in Cisco NTP output, the asterisk (*) marks the active synchronization source, while the tilde specifically denotes a statically configured server that is reachable yet not chosen as the time reference. On the CCNA 200-301 v2 exam, this tests your ability to interpret NTP synchronization status symbols, a common trap being confusion between the tilde and the plus sign (+), which represents a candidate for synchronization. A useful memory tip is to think of the tilde as a “not selected” wave, while the asterisk is the “star” of the show—the one actually syncing the router’s clock.
CCNA Network Services and Security Practice Question
This 200-301 practice question tests your understanding of network services and security. Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. A key principle to apply: nTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.. 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: A branch router receives time from an NTP server, but the show output marks the server with a tilde instead of an asterisk. What does that mean?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The server is reachable but not the one currently selected for synchronization
In Cisco NTP output, the asterisk (*) indicates the current synchronization source. The tilde (~) specifically means the server is statically configured and reachable but has not been selected for synchronization. This differs from the plus sign (+), which denotes a candidate for synchronization. Therefore, the router is not using that server as its active time source.
Key principle: NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
That server is the current system clock source
Why it's wrong here
The asterisk marks the selected synchronization source.
When this WOULD be correct
This would be correct in a question asking: 'What does an asterisk (*) next to an NTP server indicate in the show ntp associations output?'
✓
The server is reachable but not the one currently selected for synchronization
Why this is correct
It is seen by the router, but it is not the chosen source.
Related concept
NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.
✗
NTP authentication has disabled the server permanently
Why it's wrong here
The symbol alone does not mean permanent disablement.
When this WOULD be correct
If the question asked about an NTP server marked with a period (.) and the options included 'NTP authentication has disabled the server permanently,' that would be correct because a period indicates the server is unreachable or has failed authentication.
✗
The router is acting as an NTP master for that server
Why it's wrong here
That is not what the association symbol indicates.
When this WOULD be correct
This option would be correct in a scenario where the question asks: 'What does it mean if a router is configured with the ntp master command and an NTP server is also configured?' In that case, the router could act as an NTP master for that server, providing time to it.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓The server is reachable but not the one currently selected for synchronizationCorrect answer▾
Why this is correct
It is seen by the router, but it is not the chosen source.
✗That server is the current system clock sourceWrong answer — click to see why▾
Why this is wrong here
In NTP, an asterisk (*) indicates the selected time source, while a tilde (~) means the server is reachable but not selected. Option A describes the asterisk, not the tilde.
★ When this WOULD be the correct answer
This would be correct in a question asking: 'What does an asterisk (*) next to an NTP server indicate in the show ntp associations output?'
Why candidates choose this
Candidates may confuse the tilde with the asterisk symbol, or assume any reachable server is the current source without understanding NTP's selection algorithm.
✗NTP authentication has disabled the server permanentlyWrong answer — click to see why▾
Why this is wrong here
A tilde (~) indicates the server is reachable but not synchronized; a permanently disabled server due to authentication would show a period (.) or not appear at all.
★ When this WOULD be the correct answer
If the question asked about an NTP server marked with a period (.) and the options included 'NTP authentication has disabled the server permanently,' that would be correct because a period indicates the server is unreachable or has failed authentication.
Why candidates choose this
Candidates may confuse the tilde symbol with authentication failure, or they may overgeneralize that any NTP issue is due to authentication problems.
✗The router is acting as an NTP master for that serverWrong answer — click to see why▾
Why this is wrong here
In the context of NTP, a tilde (~) indicates the server is reachable but not selected as the synchronization source. The router acting as an NTP master would be indicated by the 'master' command or stratum level, not by the tilde symbol.
★ When this WOULD be the correct answer
This option would be correct in a scenario where the question asks: 'What does it mean if a router is configured with the ntp master command and an NTP server is also configured?' In that case, the router could act as an NTP master for that server, providing time to it.
Why candidates choose this
Candidates may confuse the tilde symbol with the router's role as an NTP master, or they might think that a reachable server implies the router is providing time to it, rather than receiving time from it.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
Be careful not to confuse the tilde (~) with the asterisk (*) or other symbols that indicate different statuses in NTP output.
Detailed technical explanation
How to think about this question
Network Time Protocol (NTP) is a critical IP service used to synchronize the clocks of network devices to a reliable time source. Cisco routers use NTP to maintain accurate time, which is essential for logging, security protocols, and time-sensitive operations. When a router synchronizes with an NTP server, it establishes an association, and the show ntp associations command displays these associations with symbols indicating their status.
In Cisco IOS, the asterisk (*) symbol marks the NTP server currently selected as the synchronization source, meaning the router uses that server's time to set its system clock. Other symbols, such as a tilde (~), indicate servers that are reachable and valid NTP peers but are not currently selected as the primary time source. The router prefers the server with the best synchronization quality, determined by factors like stratum level and reachability, and marks it with the asterisk, while others remain candidates.
A common exam trap is to confuse the tilde (~) symbol with the asterisk (*) or to assume it means the server is unreachable or disabled. However, the tilde simply means the server is recognized and reachable but not the active synchronization source. Understanding these symbols helps network engineers verify NTP status accurately and troubleshoot time synchronization issues effectively in Cisco environments.
KKey Concepts to Remember
NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.
The asterisk (*) symbol marks the NTP server currently selected as the router's system clock synchronization source.
A tilde (~) symbol indicates an NTP server is reachable and valid but not currently selected as the active synchronization source.
Cisco routers select the NTP server with the best stratum and reachability as the preferred synchronization source.
NTP synchronization status symbols help network engineers verify which server is actively used and which are candidates.
Misinterpreting NTP symbols can lead to incorrect assumptions about time synchronization health and troubleshooting steps.
The router does not disable or permanently reject servers marked with a tilde; they remain valid backup sources.
Understanding NTP association symbols is essential for accurate time service monitoring and troubleshooting in Cisco networks.
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
NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.
Real-world example
How this comes up in practice
A practitioner preparing for the 200-301 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. NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 200-301 question in full detail.
Review nTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status., then practise related 200-301 questions on the same topic to reinforce the concept.
Network Services and Security — This question tests Network Services and Security — NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status..
What is the correct answer to this question?
The correct answer is: The server is reachable but not the one currently selected for synchronization — In Cisco NTP output, the asterisk (*) indicates the current synchronization source. The tilde (~) specifically means the server is statically configured and reachable but has not been selected for synchronization. This differs from the plus sign (+), which denotes a candidate for synchronization. Therefore, the router is not using that server as its active time source.
What should I do if I get this 200-301 question wrong?
Review nTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status., then practise related 200-301 questions on the same topic to reinforce the concept.
What is the key concept behind this question?
NTP uses associations to represent time sources, and Cisco routers display these with symbols indicating synchronization status.
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 200-301 practice question is part of Courseiva's free Cisco 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 200-301 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.