Configure Sflow Ports Sample-Rate - Extreme Networks ExtremeWare XOS Command Reference Manual

Commands for Status Monitoring and Statistics

configure sflow ports sample-rate

configure sflow ports <portlist> sample-rate <number>
Description
Configures the sFlow per-port sampling rate.
Syntax Description
portlist
number
Default
The default number is 8192, unless modified by the
Usage Guidelines
This command configures the sampling rate on a particular set of ports, and overrides the system-wide
value set in the
configure sflow sample-rate
of two, so if 400 is specified, the sample rate is configured as 512. The valid range is 1 to 536870912.
At the hardware level, the sampling rate for all ports on a slot is the same. Ports that are configured for
fewer samples (the
number
level as ports configured for more samples. The excess samples are discarded. This mechanism is
displayed in the
show sflow {configuration}
one port is configured for a sample rate of 1024, and a second port on the same slot is configured for a
sample rate of 4096, the second port's hardware actually samples one out of 1024 packets, but only
saves the information for one out of four of those samples. In this example, the sub-sampling factor is
four.
Configuring a lower number for the sample rate means that more samples will be taken, increasing 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.
If the rate of samples going to the CPU exceeds a limit, set with the
max-cpu-sample-limit
the rate by one-half. Under those conditions, the configured rate may not be the actual rate of sampling.
The output of the
show sflow configuration
sampling.
Example
The following command sets the sample rate for the ports 4:6 to 4:10 to one packet out of every 16384:
configure sflow ports 4:6-4:10 sample-rate 16384
History
This command was first available in ExtremeWare XOS 11.0.
334
Specifies a list of ports.
Specifies the fraction (1/number) of packets to be sampled.
parameter is larger) still take the same amount of samples at the hardware
command, then the sample rate number will be doubled, effectively reducing
command will display the configured and actual rate of
configure sflow sample-rate
command. The rate is rounded off to the next power
command as the sub-sampling factor. For example, if
configure sflow
command.
ExtremeWare XOS 11.0 Command Reference Guide