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
of two, so if 400 is specified, the sample rate is configured as 512. The valid range is 1 to 536870912.
For BlackDiamond 10K only. At the hardware level, the sampling rate for all ports on a slot is the same.
Ports that are configured for fewer samples than other ports on the slot (the
still take the same amount of samples at the hardware level as ports configured for more samples. The
excess samples are discarded. This mechanism is displayed in the
command as the sub-sampling factor. For example, if 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
sample-limit
one-half. Under those conditions, the configured rate may not be the actual rate of sampling. The output
of the
show sflow configuration
For the Summit X450 only. At the hardware level, all ports on the switch are sampled at the same rate,
so if one port is configured to sample less frequently than another, the extra samples are discarded. This
is indicated in the output of the
For example, if one port is configured to sample one packet per every 8192 packets, and the second port
on the same slot is configured to sample one packet per every 16384 packets, the second port will show
a sub-sampling factor of two.
488
Specifies a list of ports.
Specifies the fraction (1/number) of packets to be sampled.
configure sflow sample-rate
command, then the sample rate number will be doubled, effectively reducing the rate by
command will display the configured and actual rate of sampling.
show sflow {configuration}
configure sflow sample-rate
command. The rate is rounded off to the next power
show sflow {configuration}
configure sflow max-cpu-
command as the sub-sampling factor.
ExtremeWare XOS 11.3 Command Reference
command.
parameter is larger)
number