Contents

Introduction· 1

Prerequisites· 1

Example: Rate limiting ICMP packets· 1

Network configuration· 1

Analysis· 1

Applicable hardware and software versions· 2

Restrictions and guidelines· 3

Procedures· 4

Verify the configuration· 4

Configuration files· 5

 

Introduction

This chapter provides examples for configuring control plane-based QoS policies.

Prerequisites

The configuration examples in this document were created and verified in a lab environment, and all the devices were started with the factory default configuration. When you are working on a live network, make sure you understand the potential impact of every command on your network.

This document assumes that you have basic knowledge of QoS policies.

Example: Rate limiting ICMP packets

Network configuration

As shown in Figure 1, the device receives a large number of ICMP packets from the Internet. As a result, CPU usage is high, and device performance degrades.

Configure a control plane-based QoS policy to meet the following requirements:

·     Rate limit ICMP packets sent to the control plane to 320 kbps.

·     Drop excess ICMP packets.

Figure 1 Network diagram

 

Analysis

To meet the network requirements, you must perform the following tasks:

·     Use the if-match command to classify ICMP packets into a class.

·     Use the car command to configure the rate limit value for ICMP packets and drop excess packets.

Applicable hardware and software versions

The following matrix shows the hardware and software versions to which this configuration example is applicable:

 

Hardware	Software version
S6812 switch series S6813 switch series	Release 66xx
S6550XE-HI switch series	Release 6008 and later
S6525XE-HI switch series	Release 6008 and later
S5850 switch series	Release 8005 and later
S5570S-EI switch series	Not supported
S5560X-EI switch series	Not supported
S5560X-HI switch series	Not supported
S5500V2-EI switch series	Not supported
MS4520V2-30F switch	Not supported
MS4520V2-30C switch MS4520V2-54C switch	Not supported
MS4520V2-28S switch MS4520V2-24TP switch	Not supported
S6520X-HI switch series S6520X-EI switch series	Not supported
S6520X-SI switch series S6520-SI switch series	Not supported
S5000-EI switch series	Not supported
MS4600 switch series	Not supported
ES5500 switch series	Not supported
S5560S-EI switch series S5560S-SI switch series	Not supported
S5500V3-24P-SI S5500V3-48P-SI	Not supported
S5500V3-SI switch series (except S5500V3-24P-SI and S5500V3-48P-SI)	Not supported
S5170-EI switch series	Not supported
S5130S-HI switch series S5130S-EI switch series S5130S-SI switch series S5130S-LI switch series	Not supported
S5120V2-SI switch series S5120V2-LI switch series	Not supported
S5120V3-EI switch series	Not supported
S5120V3-36F-SI S5120V3-28P-HPWR-SI S5120V3-54P-PWR-SI	Not supported
S5120V3-SI switch series (except S5120V3-36F-SI, S5120V3-28P-HPWR-SI, and S5120V3-54P-PWR-SI)	Not supported
S5120V3-LI switch series	Not supported
S3600V3-EI switch series	Not supported
S3600V3-SI switch series	Not supported
S3100V3-EI switch series S3100V3-SI switch series	Not supported
S5110V2 switch series	Not supported
S5110V2-SI switch series	Not supported
S5000V3-EI switch series S5000V5-EI switch series	Not supported
S5000E-X switch series S5000X-EI switch series	Not supported
E128C switch E152C switch E500C switch series E500D switch series	Not supported
MS4320V2 switch series MS4320V3 switch series MS4300V2 switch series MS4320 switch series MS4200 switch series	Not supported
WS5850-WiNet switch series	Not supported
WS5820-WiNet switch series WS5810-WiNet switch series	Not supported
WAS6000 switch series	Not supported
IE4300-12P-AC switch IE4300-12P-PWR switch IE4300-M switch series IE4320 switch series	Not supported

 

Restrictions and guidelines

When you configure a control plane-based QoS policy to rate limit ICMP packets, follow these restrictions and guidelines:

·     By default, the predefined QoS policy is applied to the control plane. The predefined QoS policy identifies packet types by system index and uses a default rate limit value for each packet type. To display the predefined QoS policy, use the display qos policy control-plane pre-defined command.

·     You can use the if-match control-plane protocol or if-match control-plane protocol-group command to classify protocol packets.

·     You can only configure the car command or a combination of the car and accounting packet commands in the behavior associated with the class.

Procedures

# Create a class named ICMP, and use the ICMP protocol as the match criterion.

<Device> system-view

[Device] traffic classifier ICMP

[Device-classifier-ICMP] if-match control-plane protocol icmp

[Device-classifier-ICMP] quit

# Create a behavior named ICMP, and configure a CAR action for ICMP packets.

[Device] traffic behavior ICMP

[Device-behavior-ICMP] car cir 320

[Device-behavior-ICMP] quit

# Create a QoS policy named ICMP, and associate the class ICMP with the behavior ICMP in the QoS policy.

[Device] qos policy ICMP

[Device-qospolicy-ICMP] classifier ICMP behavior ICMP

[Device-qospolicy-ICMP] quit

# Apply the QoS policy ICMP to the inbound direction of the control plane.

[Device] control-plane slot 1

[Device-cp-slot1] qos apply policy ICMP inbound

[Device-cp-slot1] quit

Verify the configuration

# Verify that the QoS policy is correctly applied to the control plane.

[Device] display qos policy control-plane slot 1

Control plane slot 1

  Direction: Inbound

  Policy: ICMP

   Classifier: ICMP

     Operator: AND

     Rule(s) :

      If-match control-plane protocol icmp

     Behavior: ICMP

      Committed Access Rate:

        CIR 320 (kbps), CBS 20480 (Bytes), EBS 0 (Bytes)

        Green action  : pass

        Yellow action : pass

        Red action    : discard

        Green packets : 0 (Packets)

        Red packets   : 0 (Packets)

Configuration files

#

traffic classifier ICMP operator and

 if-match control-plane protocol icmp

#

traffic behavior ICMP

 car cir 320 cbs 20480 ebs 0 green pass red discard yellow pass

#

qos policy ICMP

 classifier ICMP behavior ICMP

#

control-plane slot 1

 qos apply policy ICMP inbound