Reference Guide

sFlow | 505

sFlow

This chapter contains the following sections:

• Enable and Disable sFlow

• sFlow Show Commands

• Specify Collectors

• Polling Intervals

• Sampling Rate

• Back-Off Mechanism

• sFlow on LAG ports

• Extended sFlow

Overview

The Dell Force10 operating software (FTOS) supports sFlow version 5. sFlow is a standard-based

sampling technology embedded within switches and routers which you can use to monitor network traffic

(Figure 29-1). It is designed to provide traffic monitoring for high-speed networks with many switches and

routers. sFlow uses two types of sampling:

• Statistical packet-based sampling of switched or routed packet flows

• Time-based sampling of interface counters

The sFlow monitoring system consists of an sFlow agent (embedded in the switch/router) and an sFlow

collector. The sFlow agent resides anywhere within the path of the packet and combines the flow samples

and interface counters into sFlow datagrams and forwards them to the sFlow collector at regular intervals.

The datagrams consists of information on, but not limited to, packet header, ingress and egress interfaces,

sampling parameters, and interface counters.

Packet sampling is typically done by the application-specific integrated circuit (ASIC). sFlow collector

analyses the sFlow datagrams received from different devices and produces a network-wide view of traffic

flows.