Contents

Configuring samplers· 1

About sampler 1

Creating a sampler 1

Display and maintenance commands for a sampler 1

Samplers and IPv4 NetStream configuration examples· 2

Example: Configuring samplers and IPv4 NetStream·· 2

Configuring samplers

About sampler

A sampler selects a packet from sequential packets and sends the packet to other service modules for processing. Sampling is useful when you want to limit the volume of traffic to be analyzed. The sampled data is statistically accurate and sampling decreases the impact on the forwarding capacity of the device.

The following sampling modes are available:

·     Fixed mode—The first packet is selected from sequential packets in each sampling.

·     Random mode—Any packet might be selected from sequential packets in each sampling.

A sampler can sample packets for NetStream. Then, only the sampled packets are sent to and processed by the NetStream module. For more information about NetStream, see "Configuring NetStream."

Creating a sampler

1.     Enter system view.

system-view

2.     Create a sampler.

sampler sampler-name mode { fixed | random } packet-interval [ n-power ] rate

By default, no samplers exist.

Support for the n-power keyword varies by device model.

Display and maintenance commands for a sampler

Execute display commands in any view.

Samplers and IPv4 NetStream configuration examples

Example: Configuring samplers and IPv4 NetStream

Network configuration

As shown in Figure 1, configure samplers and NetStream as follows:

·     Configure IPv4 NetStream on the device to collect statistics on incoming and outgoing traffic.

·     Send the NetStream data to port 5000 on the NetStream server.

·     Configure fixed sampling in the inbound direction to select the first packet from 16 packets on Ten-GigabitEthernet 3/1/1.

·     Configure random sampling in the outbound direction to select one packet randomly from 16 packets on Ten-GigabitEthernet 3/1/2.

Figure 1 Network diagram

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Configuration procedure

# Create sampler samp1 in fixed sampling mode, and set the rate to 4. The first packet of 16 (2 to the 4th power) packets is selected.

<Device> system-view

[Device] sampler samp1 mode fixed packet-interval n-power 4

# Create sampler samp2 in random sampling mode, and set the sampling rate to 16. One packet from 16 packets is selected.

[Device] sampler samp2 mode random packet-interval 16

# Enable IPv4 NetStream to use sampler samp1 to collect statistics about the incoming traffic on Ten-GigabitEthernet 3/1/1.

[Device] interface ten-gigabitethernet 3/1/1

[Device-Ten-GigabitEthernet3/1/1] ip netstream inbound

[Device-Ten-GigabitEthernet3/1/1] ip netstream inbound sampler samp1

[Device-Ten-GigabitEthernet3/1/1] quit

# Enable IPv4 NetStream to use sampler samp2 to collect statistics about outgoing traffic on Ten-GigabitEthernet 3/1/2.

[Device] interface ten-gigabitethernet 3/1/2

[Device-Ten-GigabitEthernet3/1/2] ip netstream outbound

[Device-Ten-GigabitEthernet3/1/2] ip netstream outbound sampler samp2

[Device-Ten-GigabitEthernet3/1/2] quit

# Configure the address and port number of the NetStream server as the destination for the NetStream data export. Use the default source interface for the NetStream data export.

[Device] ip netstream export host 12.110.2.2 5000

Verifying the configuration

# Display configuration information for sampler samp1 and sampler samp2.

[Device] display sampler samp1

 Sampler name: samp1

  Mode: fixed;  Packet-interval: 4; IsNpower: Y

[Device] display sampler samp2

 Sampler name: samp2

  Mode: random;  Packet-interval: 16; IsNpower: N