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Status Monitoring and Statistics

ExtremeWare XOS 11.3 Concepts Guide

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for analysis. sFlow consists of a Management Information Base (MIB) and a specification of the packet

format for forwarding information to a remote agent. Details of sFlow specifications can be found in

RFC 3176, and specifications and more information can be found at the following website:

http://www.sflow.org

The ExtremeWare XOS implementation is based on sFlow version 5, which is an improvement from the

revision specified in RFC 3176. Additionally, the switch hardware allows you to set the hardware

sampling rate independently for each module on the switch, instead of requiring one global value for

the entire switch. The switch software also allows you to set the individual port sampling rates, so you

can fine-tune the sFlow statistics gathering. Per the RFC, sFlow sampling is done on ingress only.

NOTE

On the BlackDiamond 8800 family of switches, sFlow and mirroring are mutually exclusive. You can enable either

sFlow, or mirroring, but not both.

However, you should be aware of a few limitations in the current release. The current release supports:

● Generic port statistics reported to the sFlow collector

● Non-extended data

● Only those packets that do not match an ACL rule are considered for sampling

● Only port-based sampling

● No MIB support

Configuring sFlow

ExtremeWare XOS allows you to collect sFlow statistics on a per port basis. An agent, residing locally

on the switch, sends data to a collector that resides on another machine. You configure the local agent,

the address of the remote collector, and the ports of interest for sFlow statistics gathering. You can also

modify default values for how frequently on average a sample is taken and the maximum number of

samples allowed before throttling the sample gathering.

To configure sFlow on a switch, you must do the following tasks:

● Configure the local agent

● Configure the addresses of the remote collectors

● Enable sFlow globally on the switch

● Enable sFlow on the desired ports

Optionally, you may also change the default values of the following items:

● How often the statistics are collected

● How frequently a sample is taken, globally or per port

● How many samples per second can be sent to the CPU

Configuring the Local Agent

The local agent is responsible for collecting the data from the samplers and sending that data to the

remote collector as a series of UDP datagrams. The agent address is stored in the payload of the sFlow

data, and is used by the sFlow collector to identify each agent uniquely. By default, the agent uses the

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