Information About sFlow
Sampled flow (sFlow) allows you to monitor real-time traffic in data networks containing switches and routers. It uses the sampling mechanism in the sFlow agent software on switches to monitor traffic and to forward the sample data to the central data collector.
The core sFlow agent workflow goes as follows:
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Periodic polling for collecting counter sample information from the interfaces where it is enabled.
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Processing the packets received for flow sampling.
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Composing the sFlow datagram and exporting it.
sFlow Agent
The sFlow agent periodically samples or polls the interface counters that are associated with a data source of the sampled packets. The data source can be an Ethernet interface or a range of Ethernet interfaces.
When you enable sFlow sampling, based on the sampling rate and the hardware internal random number, the ingress packets and egress packets are sent to the CPU as an sFlow-sampled packet. The sFlow agent processes the sampled packets and sends an sFlow datagram to the sFlow analyzer. In addition to the original sampled packet, an sFlow datagram includes information about the ingress port, the egress port, and the original packet length. An sFlow datagram can have multiple sFlow samples.