Cisco net monitor how to#
Cisco net monitor full#
Cisco net monitor series#

Packet-based NetFlowВ sampling uses one of the two following methods to select flows for sampling and export (taken from Cisco documentation): Rather, here we are talking about вЂњflowвЂќ sampling.

The technology used here is not packet sampling in the same sense as sFlow. There are 2 types of NetFlow sampling that can be done with the Cisco 72 series.

Cisco net monitor series#

Switch(config-flow-sampler)# show samplerДЇurther details on the Nexus 7000 sampled NetFlow configuration can be found on CiscoвЂ™s web site.Д¬isco 7200 routers and Cisco 6500 series MSFCs Sampling Configuration Switch(config-if)# ip flow monitor input SampleTest Switch(config-flow-sampler)# mode 1 out-of 100 NetFlowВ sampling on the Nexus 7000 can also be configuredВ toВ sample 1 out of every X packets. вЂPacket IntervalвЂ™ sampling mode is configured.ДЎ out of every 100 packets is being sampled. Router(config-if)#ip route-cache flow sampled Router(config)#ip flow-sampling-mode packet-interval

Sampling disadvantage: billing is difficult.

Sampling advantages: CPU reduced and possible reduced exported Data.

The sampling interval is fixed and not an average.

Cisco net monitor full#

Sampled NetFlow exports the same information as full NetFlow.

Collects and exports NetFlow data for a sample of the traffic passing through the router, instead of the entire traffic.

NetFlow Sampling on the 12000В can be configured to sampleВ 1 out of every X packets. Note: You CANNOT use a Flexible Netflow monitor to sample if it is being used as a non-sampling monitor elsewhere. Router(config-if)#ip flow monitor FnF-Sampler-MON sampler mysampler-1 input Router(config)#interface fastEthernet 0/0 Router(config-sampler)# mode random 1 out-of 5 Router(config-sampler)# description Sample at 20% The example below assumes that you have already created a FnF configuration with a monitor named FnF-Sampler-MON Router(config-if)# flow-sampler mysampler1ДЇlexible NetFlow can also be used for sampling traffic. Router(config-sampler)# mode random one-out-of 100 Router(config)# flow-sampler-map mysampler1

You can define up to eight NetFlow sampler maps.

Each NetFlow sampler map can be applied to one or many subinterfaces as well as physical interfaces.

You must use separate monitors via Flexible Netflow.

Must turn off full netflow else sampling wonвЂ™t work.

Standard Netflow and Flexible Netflow options are available.

When using IOS,В 1 out of X packets are sampled as they arrive (before any NetFlow cache entries are made for those packets).

Catalyst 4948E NetFlow-Lite Packet Sampling.

7200 routers and Cisco 6500 series MSFC Sampling Configuration.

Nexus 7000 Sampling via Flexible NetFlow.

Cisco net monitor how to#

This blog will cover how to setup NetFlow Sampling on: Did you know that a sampling rate of 1 out of 100 packets reduces the export of NetFlow data by about 50 percent. High volume flow exports may also consume too much bandwidth when sent across the network. Sometimes however, 100% of the flow data is not necessary. Today, NetFlow collectors need to be able to capture and save tens of thousands of flows per second if not hundreds of thousands of flows per second.