Configuring And Enabling Sflow - Dell PowerConnect B-RX Configuration Manual

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Configuring sFlow
NOTE
sFlow does not export packets through the management port.
NOTE
sFlow does not use the management IP as the agent IP.
Sampling rate
The sampling rate is the average ratio of the number of packets incoming on an sflow enabled port,
to the number of flow samples taken from those packets. Device ports send only the sampled
traffic to the CPU. sFlow sampling requires high LP CPU usage, which can affect performance in
some configurations especially if a high sampling rate is implemented.
Inbound port monitoring
You can enable Inbound port monitoring or sFlow on ports that use the same packet processor.
However, you cannot enable both features on ports that use the same packet processor.
Extended router information
Extended router information contains information for the next hop router. This information includes
the next hop router's IP address and the outgoing VLAN ID. Extended router information also
includes the source IP address prefix length and the destination IP address prefix length.
Note that in IPv4, prefix length of source and destination IP addresses is collected only if BGP is
configured on the devices.
Extended gateway information
Extended gateway information is included in an sFlow sampled packet if BGP is enabled. The
extended gateway information includes the following BGP information about the packet's
destination route:
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NOTE
AS communities and local preferences are not included in the sampled packets.
To obtain extended gateway information use "struct extended_gateway" as described in RFC 3176.

Configuring and enabling sFlow

To configure sFlow:
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This router's autonomous system (AS) number
The route's source IP AS
The route's source peer AS
The AS path to the destination
Specify collector information. The collector is the external device to which you are exporting the
sFlow data. You can specify up to four collectors.
Optional – Change the polling interval.
Optional – Change the sampling rate.
Enable sFlow globally.
BigIron RX Series Configuration Guide
53-1001986-01