200-301 Question 365
Single answerA network administrator is tasked with configuring NTP on a Cisco router to synchronize with an external NTP server and also act as an NTP server for local devices. After configuring the NTP client and server modes, the administrator observes that the local devices are not synchronizing time with the router. Which configuration step must the administrator verify to resolve the issue?
- A
Ensure the 'ntp master' command is configured on the router.
- B
Verify that the router's clock is synchronized with the external NTP server.
- C
Check if the 'ntp authenticate' command is globally enabled on the router.
- D
Confirm that the correct NTP version is configured on the router and local devices.
Show answer and explanation
Correct answer: B
Explanation
For a Cisco router to function as an NTP server for local devices, it must first synchronize its clock with an external NTP server. If the router's clock is not synchronized, it will not distribute time to local devices. Verifying the synchronization status with the external NTP server is the most critical step in resolving the issue described.
- A. Incorrect.
The 'ntp master' command is used to configure the router as a standalone NTP server, even without synchronization to an external NTP server. However, in this scenario, the router is configured as a client to synchronize with an external NTP server, so this is not required.
- B. Correct.
If the router's clock is not synchronized with the external NTP server, it cannot provide accurate time to local devices as an NTP server. This is the critical issue that must be verified to resolve the problem.
- C. Incorrect.
The 'ntp authenticate' command is used for enabling authentication of NTP messages. While important for security, it is not required to resolve the issue of local devices not synchronizing with the router.
- D. Incorrect.
The NTP version mismatch can cause synchronization issues in some advanced cases, but it is not the primary issue described in this scenario.