NetFlow is a network protocol designed to collect and monitor network traffic. It provides information about the source and destination of traffic, the types of traffic, and the amount of traffic flowing through the network. Here are some common troubleshooting scenarios for NetFlow:
1. NetFlow is not collecting data: If you are not seeing any data in your NetFlow collector, check the configuration on your routers and switches. Make sure that NetFlow is enabled on the interfaces that you want to monitor, and that the correct version of NetFlow is being used (v5, v9, or flexible NetFlow). Also, make sure that the collector is configured to receive data from the devices.
2. NetFlow data is incomplete: If you are seeing some data in your NetFlow collector, but it is incomplete, check to see if there are any ACLs or filters that could be blocking traffic. Also, check the configuration on your devices to ensure that they are correctly exporting NetFlow data.
3. NetFlow data is inaccurate: If you are seeing inaccurate data in your NetFlow collector, it could be due to a misconfiguration on the devices or the collector. Check to see if the correct IP addresses and port numbers are being used, and that the time settings on the devices are correct.
4. NetFlow is using too much CPU: If you notice that your devices are using too much CPU when NetFlow is enabled, you can reduce the amount of data being collected by configuring NetFlow sampling or filtering. Sampling allows you to collect data from a subset of packets, while filtering allows you to exclude certain types of traffic from being collected.
5. NetFlow is not supported on all devices: NetFlow is not supported on all devices, especially older devices. In some cases, you may need to use a different protocol, such as sFlow, to monitor network traffic.
4.7 Troubleshoot network problems using Cisco DNA Center assurance (connectivity, monitoring, device health, network health)
Cisco DNA Center is a network management platform that provides end-to-end network visibility, automation, and assurance for enterprise networks. The assurance component of Cisco DNA Center provides continuous monitoring and analysis of the network to identify and troubleshoot issues.
Connectivity issues: Cisco DNA Center can identify connectivity problems and help troubleshoot the root cause of the issue, such as a misconfigured switch port or a routing issue.
Performance issues: Cisco DNA Center can monitor network performance metrics, such as latency and packet loss, and alert network administrators if performance falls below acceptable levels.
Device health: Cisco DNA Center can monitor the health of network devices, such as switches and routers, and alert administrators if a device is not operating correctly.
Network health: Cisco DNA Center can analyze network traffic patterns and identify areas of congestion or network bottlenecks, allowing administrators to optimize network performance.
To troubleshoot network problems using Cisco DNA Center assurance, administrators can use the platform's dashboard to view network performance and health metrics, configure alerts for specific events, and use the platform's analytics capabilities to identify and diagnose issues. The platform can also provide recommendations for resolving issues and optimizing network performance.
