Configuring sflow from Extreme Switches

The following commands configure an example Extreme Networks switch (10.0.0.246), sampling packets at 1-in-512, polling counters every 30 seconds and sending the sFlow to an analyzer (10.0.0.50) over UDP using the default sFlow port (6343):

enable sflow 

This command allows you to configure the IP address of the sflow agent. This is normally set to the IP that identifies the switch in your NMS.

configure sflow agent   <ip_addr>

• configure sflow agent 10.0.0.246

Configure the collector

configure sflow collector <ip_addr> {port udp-port-number} vr <vr_name>

• configure sflow collector 10.0.0.50 port 6343   vr vr_name

You can then specify the poll interval in seconds

configure sflow poll-interval <seconds> (which can be between 0 – 3600 seconds, note the default at 20 seconds)

• configure sflow poll-interval 30

configure sflow sample-rate (this configures the default rate at which samples will occur on newly enabled sflow ports and not already existing ports)

the default is 8192 but can be set to 256 to 536870912 (all powers of 2, so if it is set at 400, it will automate to a sample rate of every 512 packets)

• configure sflow sample-rate 512
• enable sflow backoff-threshold
• configure sflow backoff-threshold 100
• enable sflow ports all

Configure sFlow monitoring on all interfaces on the switch for full visibility. Packet sampling is implemented in hardware so all the interfaces can be monitored with very little overhead.

The lower the sampling rate the better for the CCE and the OTM.  Please use as low a rate as possible.  Such as: sample rate 100

Note: Extreme Networks switches support automatic back-off of sampling rates based on a settable samples-per-second threshold.This mechanism ensures that an aggressively selected sampling rate will not generate excessive numbers of samples (see sFlow Version 5, section 4.2.2).