Contents

Configuring samplers· 1

Creating a sampler 1

Displaying and maintaining a sampler 1

Sampler configuration example· 1

Network requirements· 1

Verifying the configuration· 2

Configuring samplers

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

Displaying and maintaining a sampler

Execute display commands in any view.

Sampler configuration example

Network requirements

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 256 packets on GigabitEthernet 2/1/1.

·     Configure random sampling in the outbound direction to select one packet randomly from 1024 packets on GigabitEthernet 2/1/2.

Figure 1 Network diagram

Configuration procedure

# Create sampler 256 in fixed sampling mode, and set the rate to 8. The first packet of 256 (2 to the 8th power) packets is selected.

<Device> system-view

[Device] sampler 256 mode fixed packet-interval n-power 8

# Create sampler 1024 in random sampling mode, and set the sampling rate to 1024. One packet from 1024 packets is selected.

[Device] sampler 1024 mode random packet-interval 1024

# Enable IPv4 NetStream to use sampler 256 to collect statistics about the incoming traffic on GigabitEthernet 2/1/1.

[Device] interface gigabitethernet 2/1/1

[Device-GigabitEthernet2/1/1] ip netstream inbound

[Device-GigabitEthernet2/1/1] ip netstream inbound sampler 256

[Device-GigabitEthernet2/1/1] quit

# Enable IPv4 NetStream to use sampler 1024 to collect statistics about outgoing traffic on GigabitEthernet 2/1/2.

[Device] interface gigabitethernet 2/1/2

[Device-GigabitEthernet2/1/2] ip netstream outbound

[Device-GigabitEthernet2/1/2] ip netstream outbound sampler 1024

[Device-GigabitEthernet2/1/2] 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 256 and sampler 1024.

[Device] display sampler 256

 Sampler name: 256

  Mode: Fixed;  Packet-interval: 8; IsNpower: Y

[Device] display sampler 1024

 Sampler name: 1024

  Mode: Random;  Packet-interval: 1024; IsNpower: N