Sflow; Overview; Implementation Information - Dell S6100 Configuration Manual

Hide thumbs Also See for S6100:

Table of Contents

sFlow is a standard-based sampling technology embedded within switches and routers which is used to monitor network traffic. It is

designed to provide traffic monitoring for high-speed networks with many switches and routers.

Enabling Extended sFlow

Enabling and Disabling sFlow on an Interface

Enabling sFlow Max-Header Size Extended

sFlow Show Commands

Configuring Specify Collectors

Changing the Polling Intervals

Back-Off Mechanism

sFlow on LAG ports

Enabling Extended sFlow

The Dell Networking Operating System (OS) supports sFlow version 5.

sFlow is a standard-based sampling technology embedded within switches and routers which is used to monitor network traffic. 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 consist of information on, but not limited to, packet header, ingress and egress

interfaces, sampling parameters, and interface counters.

Application-specific integrated circuits (ASICs) typically complete packet sampling. sFlow collector analyses the sFlow datagrams received

from different devices and produces a network-wide view of traffic flows.

Implementation Information

Dell Networking sFlow is designed so that the hardware sampling rate is per line card port-pipe and is decided based on all the ports in that

If you do not enable sFlow on any port specifically, the global sampling rate is downloaded to that port and is to calculate the port-pipe's

lowest sampling rate. This design supports the possibility that sFlow might be configured on that port in the future. Back-off is triggered

based on the port-pipe's hardware sampling rate.

For example, if port 1 in the port-pipe has sFlow configured with a 16384 sampling rate while port 2 in the port-pipe has sFlow configured

but no sampling rate set, the system applies a global sampling rate of 512 to port 2. The hardware sampling rate on the port-pipe is then set

at 512 because that is the lowest configured rate on the port-pipe. When a high traffic situation occurs, a back-off is triggered and the

sFlow