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how hard is ccna exam.FlexibleNetFlow adds a new NetFlowv9 export format field type for header and packet part types. Devices with the Flexible NetFlow feature enabled communicate with the collector using the NetFlow v9 export template field.When you configure FlexibleNetFlow, execute the flowmonitor command in the interface configuration mode of the network device to allow the device to exercise the network traffic monitoring function. During the execution of flowmonitoring, the network device captures flow data from the network flow and adds it to the flow monitor cache based on the key and non-key segments in the flow record.The entity that exports the data from the stream monitor cache to the remote system is called a stream exporter (flowexporter). o The stream exporter is configured as a separate entity. The stream exporter is assigned to the stream monitor. Network administrators can create multiple stream exporters and assign them to one or more stream monitors. The flow exporter includes the destination address of the reporting server, the transport layer protocol type (User Datagram Protocol [UDP] or Flow Control Transport Protocol [SCTP]), and the export format corresponding to the NetFlow version or IPFIX.Note: You can configure up to eight flow exporters per flow monitor.The flow sampler is created as a separate component when configuring the router. The load on devices with FlexibleNetFlow enabled can be reduced by having the flow sampler limit the data of the packets that play a role in analysis.Flow sampling trades off monitoring accuracy for router performance. Applying a flow sampler to a flow monitor reduces the load on the router performing the flow monitor function, because it also reduces the number of packets that the flow monitor has to analyze. Reducing the number of packets analyzed by the stream monitor inevitably reduces the accuracy of the information stored in the stream monitor cache.The following step-by-step guide shows you how to enable and configure the Flexible NetFlow feature on Cisco IOS and Cisco IOS-XE devices. Figure 11-24 shows the configuration steps to enable the Flexible NetFlow feature.Figure 11-24 Configuration Steps for Enabling the Flexible NetFlow Function The configuration steps are shown below. Step 1. configure flow logging.11.2 Network Insight Technologies 435Step 2. configure the flow monitor. Step 3. Configure the flow exporter for the flow monitor. Step 4. apply the stream monitor to the interface. The topology in Figure 11-25 is used as an example to demonstrate how to enable the Flexible NetFlow feature. Configure the Cisco router (R1) deployed in the Raleigh, North Carolina, branch office to enable the FlexibleNetFlow feature.