Netgear XCM8806 Chassis User Manual - Page 231

NETGEAR 8800 User Manual enable sflow ports You may enable and disable sFlow on ports irrespective of the global state of sFlow, but samples are not taken until both the port state and the global state are enabled. To disable sFlow on ports, use the following command: disable sflow ports Additional sFlow Configuration Options You can configure three global options to different values from the defaults. These options affect how frequently the sFlow data is sent to the remote collector, how frequently packets are sampled, and the maximum number of sFlow samples that could be processed in the CPU per second. You can also configure how frequently packets are sampled per port. Polling Interval Each port counter is periodically polled to gather the statistics to send to the collector. If there is more than one counter to be polled, the polling is distributed in such a way that each counter is visited once during each polling interval, and the data flows are spaced in time. For example, assume that the polling interval is 20 seconds and there are 40 counters to poll. Two ports will be polled each second, until all 40 are polled. To configure the polling interval, use the following command: configure sflow poll-interval Global Sampling Rate The global sampling rate is the rate that newly enabled sFlow ports will have their sample rate set to. Changing this rate does not affect currently enabled sFlow ports. The default sample rate is 8192, so by default sFlow samples one packet out of every 8192 received. To configure the switch to use a different sampling rate, use the following command: configure sflow sample-rate For example, if you set the sample rate number to 16384, the switch samples one out of every 16384 packets received. Higher numbers mean fewer samples and longer times between samples. If you set the number too low, the number of samples can be very large, which increases the load on the switch. Do not configure the sample rate to a number lower than the default unless you are sure that the traffic rate on the source is low. The minimum rate that these platforms sample is 1 out of every 256 packets. If you configure a rate to be less than 256, the switch automatically rounds up the sample rate to 256. Per Port Sampling Rate The per port sampling rate overrides the system-wide value set in the configure sflow sample-rate command. The rate is rounded off to the next power of two, so if 400 is specified, the sample rate is configured as 512. The valid range is 1 to 536870912. To set the sampling rate on individual ports, use the following command: Chapter 8. Status Monitoring and Statistics | 231