300-410 Question 284
Select 2An enterprise network engineer has configured Flexible NetFlow on a router to collect traffic statistics for analysis. However, the NetFlow collector is not receiving any data. The engineer has verified that the NetFlow configuration is applied to the correct interfaces, and the flow export destination is correctly configured. Which of the following could be the causes of this issue?
- A
The flow exporter uses an incorrect transport protocol.
- B
The flow monitor is not attached to the interface.
- C
The NetFlow version configured on the collector does not match the router's configuration.
- D
The router does not have sufficient resources to process NetFlow data.
- E
The flow record is missing required fields for exporting traffic data.
Show answer and explanation
Correct answers: B, C
Explanation
For Flexible NetFlow to export data successfully, the flow monitor must be attached to the interface where traffic is being observed, and the NetFlow version on the router must match the collector's configuration. These two factors are common causes of issues when NetFlow data is not received by the collector.
- A. Incorrect.
Incorrect transport protocol (such as TCP vs. UDP) is not a typical issue for NetFlow, as NetFlow exports typically use UDP by default. This is unlikely to be the cause.
- B. Correct.
If the flow monitor is not attached to the interface, no NetFlow data will be collected or exported, even if the rest of the configuration is correct.
- C. Correct.
If the NetFlow version configured on the collector does not match the router's configuration (e.g., v5 vs. v9), the collector will not be able to interpret the exported data properly.
- D. Incorrect.
While resource constraints on the router can impact performance, it is less likely to completely prevent data export unless the router is under significant load or misconfigured.
- E. Incorrect.
The flow record does not need specific fields for exporting traffic data, as long as the flow record is valid and matches the intended use case.