Counter Polling By The Sflow Agent; Sflow Collector; Configuring Sflow Receiver Instances; Sflow Instances - HP ProCurve 530 NA (J8986A) Management And Configuration Manual

Special Features
sFlow
sFlow datagrams are compact and do not require a large amount of network
bandwidth. The sampled packets are approximately 7 percent of the original
packet size, and several samples can fit in a single datagram. Extra space at
the end of the datagram is filled with the counters reported by polled radios
"Counter Polling by the sFlow Agent" on page 8-13). Since only some packets are
(see
sampled, sFlow creates very little overhead. For example, if you set the
sampling rate to one packet in 100, flow sampling only adds about 0.7 percent
overhead.
The Access Point 530 uses datagram version 5, and you can specify the size of
the datagram when you configure sFlow.

Counter Polling by the sFlow Agent

In addition to sampling every "nth" packet, the Access Point 530's sFlow agent
can sample the counters tracked by the three interfaces. These counters
include traffic statistics such as the number of inbound packets, outbound
packets, and retransmitted frames.
The sFlow agent obtains the counters by polling the interfaces periodically,
as needed to fill datagrams most efficiently. However, you can configure the
maximum time that can elapse before an interface must be polled.

sFlow Collector

The sFlow collector, which receives samples from agents all over the network,
combines and analyzes the samples to produce a picture of network activity.
An example of an sFlow collector is ProCurve Manager Plus (PCM Plus).

Configuring sFlow Receiver Instances

An sFlow receiver manages the sFlow agent. The sFlow receiver is an sFlow
collector that has opened a session with the sFlow agent and taken responsi-
bility for receiving datagrams from that agent. To manage the agent, the
receiver typically uses the SNMP protocol and the MIB for sFlow. The Access
Point 530's sFlow MIB version is 1.3.

sFlow Instances

The Access Point 530 sFlow agent provides three instances for sFlow
receivers. Under SNMP, the sFlow collector contacts the access point's agent
and uses SNMP to reserve and configure a receiver instance.
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