FastNetMon sFlow configuration

You may find sFlow protocol in wide range of switches. Some models of routers also offer it as option. One of the key benefits of sFlow is an ability to detect DDoS in few seconds.

You can enable sFlow support in FastNetMon with few easy steps.

Enable sFlow plugin:

Specify port / ports for sFlow capture (6343 is default port):

Specify interface for listening ( is default):

Apply changes and restart FastNetMon:

After that you have to configure sFlow on sFlow agent’s side (switch, router, server) to configured port and host.

We have our own guides for configuring sFlow:

According to amount of traffic in network we suggest following sampling rates:

BandwidthSampling rate
100 Mbit500
1 Gbit1000
10 Gbit2000

After finishing configuration from agent’s side, you may check that FastNetMon receives data using our counters:

It’s very important to keep reasonable sampling rate for accurate bandwidth calculation. In some cases during traffic spikes switches can increase sampling rate over value specified in configuration. FastNetMon has an option to expose sampling rate for each router. You can enable it this way:

After enabling this option, you can check sampling rate for each device and line card this way: