Cisco Nexus 5000 NX-OS Service Configuration Manual

Cisco Nexus 5000 NX-OS Quality of Service Configuration Guide, Release 5.1(3)N2(1)

First Published: March 13, 2012

Last Modified: February 12, 2013

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Text Part Number: OL-26657-01

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CONTENTS

Preface

CHAPTER 1

CHAPTER 2

CHAPTER 3

Preface vii

Audience vii

Document Conventions vii

Documentation Feedback viii

Obtaining Documentation and Submitting a Service Request ix

New and Changed Information 1

New and Changed Information for this Release 1

Overview 3

Information About Quality of Service 3

Modular QoS CLI 3

QoS for Traffic Directed to the CPU 5

Configuring Classification 7

Information About Classification 7

Ingress Classification Policies 8

Licensing Requirements for Classification 8

Configuring Classification 8

Configuring Class Maps 8

Configuring CoS Classification 9

Configuring Precedence Classification 10

Configuring DSCP Classification 12

Configuring Protocol Classification 13

Configuring IP RTP Classification 14

Configuring ACL Classification 15

Verifying the Classification Configuration 16

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Contents

CHAPTER 4

CHAPTER 5

Configuring Policy Maps 17

Information About Policy Types 17

Configuring Policy Maps 19

Creating Policy Maps 19

Configuring Type QoS Policies 21

Configuring Type Network QoS Policies 22

Configuring Type Queuing Policies 23

Verifying the Policy Map Configuration 24

Configuring Marking 27

Information About Marking 27

Configuring Marking 27

Configuring DSCP Marking 27

Configuring IP Precedence Marking 29

Configuring CoS Marking 30

Required CoS Marking Configuration in a Layer 3 Topology 31

CHAPTER 6

CHAPTER 7

Verifying the Marking Configuration 32

Configuring QoS on the System 35

Information About System Classes 35

System Classes 35

Default System Classes 35

MTU 36

Configuring System QoS 37

Attaching the System Service Policy 37

Restoring the Default System Service Policies 38

Configuring the Queue Limit for a Specified Fabric Extender 39

Enabling the Jumbo MTU 40

Verifying the Jumbo MTU 41

Verifying the System QoS Configuration 41

Configuring QoS on Interfaces 43

Information About Interface QoS 43

Trust Boundaries 43

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Contents

Policy for Fibre Channel Interfaces 44

QoS for Multicast Traffic 44

Configuring Interface QoS 45

Configuring Untagged CoS 45

Configuring an Interface Service Policy 45

Configuring a Service Policy for a Layer 3 Interface 46

Verifying the Interface QoS Configuration 47

CHAPTER 8

Configuring QoS on VLANs 49

Information About VLAN QoS 49

Precedence of QoS Policies 49

Example of Interface, System, and VLAN Policy Precedence 50

Example of Interface and System QoS Policy Precedence 50

Example of System and VLAN Policy Precedence 50

Example of VLAN QoS and VACL Policy Precedence 51

Limiting TCAM Entries for VLAN QoS 52

Guidelines and Limitations for VLAN QoS 52

Configuring VLAN QoS 53

Configuring or Changing the Interface QoS TCAM Limit 53

Removing the Interface QoS Limit from the TCAM 54

Configuring a Service Policy on a VLAN 54

Removing a Service Policy from a VLAN 55

Verifying the VLAN QoS Configuration 56

Feature History for VLAN QoS 56

CHAPTER 9

Configuring Queuing and Flow Control 57

Information About Queues 57

Ingress Queuing Policies 57

Egress Queuing Policies 57

Buffering and Queue Limits on the Cisco Nexus 5000 Platform 58

Buffering and Queue Limits on the Cisco Nexus Device 59

Information About Flow Control 60

Link-Level Flow Control 60

Priority Flow Control 60

Configuring Queuing 61

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Contents

Configuring the Queue Limit for a Specified Fabric Extender 61

Configuring No-Drop Buffer Thresholds 62

Configuring the Buffer Threshold for the Cisco Nexus 2148T Fabric Extender 63

Enabling Virtual Output Queuing Limits for Unicast Traffic on the Cisco Nexus Device 64

Configuring Flow Control 65

Link-Level Flow Control 65

Configuring Priority Flow Control 65

Configuring Link-Level Flow Control 66

Disabling Slow Port Pruning on Multicast Traffic on the Cisco Nexus 5500 Series

Device 66

Verifying the Queue and Flow Control Configurations 67

CHAPTER 10

QoS Configuration Examples 69

QoS Example 1 69

QoS Example 2 70

QoS Example 3 72

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Preface

The Preface contains the following sections:

Audience, page vii

•

Document Conventions, page vii

•

Documentation Feedback, page viii

•

Obtaining Documentation and Submitting a Service Request, page ix

•

Audience

This publication is for network administrators who configure and maintain Cisco Nexus devices and Cisco
Nexus 2000 Series Fabric Extenders.

Document Conventions

Command descriptions use the following conventions:

DescriptionConvention

bold

Italic

[x | y]

{x | y}

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Bold text indicates the commands and keywords that you enter literally
as shown.

Italic text indicates arguments for which the user supplies the values.

Square brackets enclose an optional element (keyword or argument).[x]

Square brackets enclosing keywords or arguments separated by a vertical
bar indicate an optional choice.

Braces enclosing keywords or arguments separated by a vertical bar
indicate a required choice.

Documentation Feedback

Preface

DescriptionConvention

[x {y | z}]

Nested set of square brackets or braces indicate optional or required
choices within optional or required elements. Braces and a vertical bar
within square brackets indicate a required choice within an optional
element.

variable

Indicates a variable for which you supply values, in context where italics
cannot be used.

string

A nonquoted set of characters. Do not use quotation marks around the
string or the string will include the quotation marks.

Examples use the following conventions:

DescriptionConvention

Terminal sessions and information the switch displays are in screen font.screen font

Information you must enter is in boldface screen font.boldface screen font

italic screen font

Arguments for which you supply values are in italic screen font.

Nonprinting characters, such as passwords, are in angle brackets.< >

Default responses to system prompts are in square brackets.[ ]

!, #

This document uses the following conventions:

Note

Means reader take note. Notes contain helpful suggestions or references to material not covered in the
manual.

Caution

Means reader be careful. In this situation, you might do something that could result in equipment damage
or loss of data.

Documentation Feedback

To provide technical feedback on this document, or to report an error or omission, please send your comments
to: [e-mail].

We appreciate your feedback.

An exclamation point (!) or a pound sign (#) at the beginning of a line
of code indicates a comment line.

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Preface

Obtaining Documentation and Submitting a Service Request

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service
request, and gathering additional information, see What's New in Cisco Product Documentation, at: http://

www.cisco.com/c/en/us/td/docs/general/whatsnew/whatsnew.html.

Subscribe to What's New in Cisco Product Documentation, which lists all new and revised Cisco technical
documentation as an RSS feed and delivers content directly to your desktop using a reader application. The
RSS feeds are a free service.

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Obtaining Documentation and Submitting a Service Request

Preface

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CHAPTER 1

New and Changed Information

This chapter contains the following sections:

New and Changed Information for this Release, page 1

•

New and Changed Information for this Release

The following table provides an overview of the significant changes to this guide for this current release. The
table does not provide an exhaustive list of all changes made to the configuration guide or of the new features
in this release.

Where DocumentedDescriptionFeature

Support for QoS VLANs.VLAN QoS

Configuring QoS on VLANs, on
page 49

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New and Changed Information for this Release

New and Changed Information

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Overview

This chapter contains the following sections:

Information About Quality of Service, page 3

•

Modular QoS CLI, page 3

•

QoS for Traffic Directed to the CPU , page 5

•

Information About Quality of Service

The configurable Cisco NX-OS quality of service (QoS) features allow you to classify the network traffic,
prioritize the traffic flow, and provide congestion avoidance.

The default QoS configuration on the device provides lossless service for Fibre Channel and Fibre Channel
over Ethernet (FCoE) traffic and best-effort service for Ethernet traffic. QoS can be configured to provide
additional classes of service for Ethernet traffic. Cisco NX-OS QoS features are configured using Cisco
Modular QoS CLI (MQC).

Standard Ethernet is a best-effort medium which means that it lacks any form of flow control. In the event of
congestion or collisions, Ethernet will drop packets. The higher level protocols detect the missing data and
retransmit the dropped packets.

Fibre Channel requires a reliable transport system that guarantees the delivery of every packet. To properly
support FCoE, Ethernet has been enhanced with a priority flow control (PFC) mechanism to prevent congestion.

The FCoE QoS must be configured either if native FC or FCoE or FC and FCoE are in use. The FCoE QoS
must be added even if Ethernet is not configured on the switch.

The following commands will enable the default QoS configuration:

switch(config)# system qos
switch(config-sys-qos)# service-policy type queuing input fcoe-default-in-policy
switch(config-sys-qos)# service-policy type queuing output fcoe-default-out-policy
switch(config-sys-qos)# service-policy type qos input fcoe-default-in-policy
switch(config-sys-qos)# service-policy type network-qos fcoe-default-nq-policy

CHAPTER 2

Modular QoS CLI

The Cisco Modular QoS CLI (MQC) provides a standard set of commands for configuring QoS.

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Modular QoS CLI

Overview

You can use MQC to define additional traffic classes and to configure QoS policies for the whole system and
for individual interfaces. Configuring a QoS policy with MQC consists of the following steps:

1

Define traffic classes.

2

Associate policies and actions with each traffic class.

3

Attach policies to logical or physical interfaces as well as at the global system level.

MQC provides two command types to define traffic classes and policies:

class-map

Defines a class map that represents a class of traffic based on packet-matching criteria. Class maps are
referenced in policy maps.

The class map classifies incoming packets based on matching criteria, such as the IEEE 802.1p class
of service (CoS) value. Unicast and multicast packets are classified.

policy-map

Defines a policy map that represents a set of policies to be applied on a class-by-class basis to class
maps.

The policy map defines a set of actions to take on the associated traffic class, such as limiting the
bandwidth or dropping packets.

Note

You define the following class-map and policy-map object types when you create them:

network-qos

Defines MQC objects that you can use for system level related actions.

qos

Defines MQC objects that you can use for classification.

queuing

Defines MQC objects that you can use for queuing and scheduling.

The qos type is the default for the class-map and policy-map commands, but not for the service-policy
which requires that you specify an explicit type.

You can attach policies to interfaces or EtherChannels as well as at the global system level by using the
service-policy command.

You can view all or individual values for MQC objects by using the show class-map and show policy-map
commands.

An MQC target is an entity (such as an Ethernet interface) that represents a flow of packets. A service policy
associates a policy map with an MQC target and specifies whether to apply the policy on incoming or outgoing
packets. This mapping enables the configuration of QoS policies such as marking, bandwidth allocation,
buffer allocation, and so on.

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Overview

QoS for Traffic Directed to the CPU

The device automatically applies QoS policies to traffic that is directed to the CPU to ensure that the CPU is
not flooded with packets. Control traffic, such as bridge protocol data units (BPDU) frames, is given higher
priority to ensure delivery.

QoS for Traffic Directed to the CPU

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QoS for Traffic Directed to the CPU

Overview

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Configuring Classification

This chapter contains the following sections:

Information About Classification, page 7

•

Ingress Classification Policies, page 8

•

Licensing Requirements for Classification, page 8

•

Configuring Classification, page 8

•

Verifying the Classification Configuration, page 16

•

Information About Classification

Classification is the separation of packets into traffic classes. You configure the device to take a specific action
on the specified classified traffic, such as policing or marking down, or other actions.

You can create class maps to represent each traffic class by matching packet characteristics with classification
criteria.

CHAPTER 3

Table 1: Classification Criteria

DescriptionClassification Criteria

Criteria specified in a named class-map object.Class map

Precedence

Differentiated Services Code Point (DSCP)

Protocol

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Precedence value within the Type of Service (ToS)
byte of the IP Header.

DSCP value within the DIffServ field of the IP
Header.

Selected set of protocols, including Address
Resolution Protocol (ARP) and Connectionless
Network Service (CLNS).

Ingress Classification Policies

Configuring Classification

DescriptionClassification Criteria

IP RTP

ACL

Table 2: Supported RFCs

RFC 2474

Ingress Classification Policies

You use classification to partition traffic into classes. You classify the traffic based on the packet property
(CoS field) or the packet header fields that include IP precedence, Differentiated Services Code Point (DSCP),
and Layer 2 to Layer 4 parameters. The values used to classify traffic are called match criteria.

Traffic that fails to match any class is assigned to a default class of traffic called class-default.

Identify applications using Real-time Transport
Protocol (RTP) by UDP port number range.

Traffic is classified by the criteria defined in the
access control list (ACL).

TitleRFC

Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers

Licensing Requirements for Classification

This feature does not require a license. Any feature not included in a license package is bundled with the Cisco
NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco
NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.

Configuring Classification

Configuring Class Maps

You can create or modify a class map with the class-map command. The class map is a named object that
represents a class of traffic. In the class map, you specify a set of match criteria for classifying the packets.
You can then reference class maps in policy maps.

The class map type default is type qos and its match criteria default is match-all.Note

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Configuring Classification

Configuring CoS Classification

Procedure

PurposeCommand or Action

Step 1

Step 2

Step 3

switch(config)# class-map
[type {network-qos | qos |
queuing}] class-map name

switch(config)# class-map
[type qos] [match-all |
match-any] class-map name

Enters global configuration mode.switch# configure terminal

Creates or accesses a named object that represents the specified class
of traffic.

Class-map names can contain alphabetic, hyphen, or underscore
characters, are case sensitive, and can be up to 40 characters.

The three class-map configuration modes are as follows:

• network-qos—Network-wide (global) mode. CLI prompt:

switch(config-cmap-nq)#

• qos—Classification mode; this is the default mode. CLI

prompt: switch(config-cmap-qos)#

• queuing—Queuing mode. CLI prompt:

switch(config-cmap-que)#

(Optional)
Specifies that packets must match any or all criteria that is defined
for a class map.

• match-all—Classifies traffic if packets match all criteria that

is defined for a specified class map (for example, if both the
defined CoS and the ACL criteria match).

• match-any—Classifies traffic if packets match any criteria

that is defined for a specified class map (for example, if either
the CoS or the ACL criteria matches).

Class-map names can contain alphabetic, hyphen, or underscore
characters, are case sensitive, and can be up to 40 characters.

Step 4

switch(config)# no class-map
[type {network-qos | qos |
queuing}] class-name

(Optional)
Deletes the specified class map.

Note

You cannot delete the two system-defined class maps:

class-fcoe and class-default.
Class-map names can contain alphabetic, hyphen, or underscore
characters, are case sensitive, and can be up to 40 characters.

Configuring CoS Classification

You can classify traffic based on the class of service (CoS) in the IEEE 802.1Q header. This 3-bit field is
defined in IEEE 802.1p to support QoS traffic classes. CoS is encoded in the high order 3 bits of the VLAN
ID Tag field and is referred to as user_priority.

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Configuring Precedence Classification

The Cisco Nexus 2148 Fabric Extender does not support frames with the dot1p vlan 0 tag.Note

If a system class is configured with a no-drop function, the match cos command serves an additional purpose.
The switch sends the CoS value to the adapter so that the adapter will apply a PFC pause for this CoS value.

The FCoE system class has a default CoS value of 3. You can add a match cos configuration to the FCoE
system class to set a different CoS value. A PFC pause will be applied to traffic that matches the new value.

Procedure

Configuring Classification

PurposeCommand or Action

Step 1

Step 2

switch(config)# class-map type
qos class-name

Enters global configuration mode.switch# configure terminal

Creates a named object that represents a class of traffic.
Class-map names can contain alphabetic, hyphen, or
underscore characters, are case sensitive, and can be up to 40
characters.

Step 3

switch(config-cmap-qos)# match
cos cos-value

Specifies the CoS value to match for classifying packets into
this class. You can configure a CoS value in the range of 0
to 7.

Note

When a Cisco Nexus 2148T Fabric Extender is
connected and in use, data traffic should never be
marked with a CoS value of 7. CoS 7 is reserved for
control traffic transiting the Fabric Extender.

Step 4

switch(config-cmap-qos)# no
match cos cos-value

(Optional)
Removes the match from the traffic class.

This example shows how to classify traffic by matching packets based on a defined CoS value:

switch# configure terminal
switch(config)# class-map type qos match-any class_cos
switch(config-cmap-qos)# match cos 4, 5-6

Use the show class-map command to display the CoS value class-map configuration:

switch# show class-map class_cos

Configuring Precedence Classification

You can classify traffic based on the precedence value in the type of service (ToS) byte field of the IP header
(either IPv4 or IPv6). The following table shows the precedence values:

Table 3: Precedence Values

List of Precedence ValuesValue

IP precedence value<0-7>

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Configuring Classification

Configuring Precedence Classification

List of Precedence ValuesValue

Critical precedence (5)critical

Flash precedence (3)flash

Flash override precedence (4)flash-override

Immediate precedence (2)immediate

internet

Procedure

Step 1

Step 2

Step 3

switch(config)# class-map type qos
match-any class-name

switch(config-cmap-qos)#match
precedence precedence-values

Internetwork control precedence
(6)

Network control precedence (7)network

Priority precedence (1)priority

Routine precedence (0)routine

PurposeCommand or Action

Enters global configuration mode.switch# configure terminal

Creates a named object that represents a class of traffic.
Class-map names can contain alphabetic, hyphen, or
underscore characters, are case sensitive, and can be up
to 40 characters.

Configures the traffic class by matching packets based
on precedence values. For a list of precedence values,
see the Precedence Values table.

Step 4

switch((config-cmap-qos)# no match
precedence precedence-values

(Optional)
Removes the match from the traffic class. For a list of
precedence values, see the Precedence Values table.

This example shows how to classify traffic by matching packets based on the precedence value in the ToS
byte field of the IP header:

switch# configure terminal
switch(config)# class-map type qos match-any class_precedence
switch(config-cmap-qos)# match precedence 1-2, critical

Use the show class-map command to display the IP precedence value class-map configuration:

switch# show class-map class_precedence

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Configuring DSCP Classification

Configuring DSCP Classification

You can classify traffic based on the Differentiated Services Code Point (DSCP) value in the DiffServ field
of the IP header (either IPv4 or IPv6).

Table 4: Standard DSCP Values

Configuring Classification

List of DSCP ValuesValue

af11

af12

af13

af21

af22

af23

af31

af32

af33

af41

af42

af43

AF11 dscp (001010)—decimal value 10

AF12 dscp (001100)—decimal value 12

AF13 dscp (001110)—decimal value 14

AF21 dscp (010010)—decimal value 18

AF22 dscp (010100)—decimal value 20

AF23 dscp (010110)—decimal value 22

AF31 dscp (011010)—decimal value 26

AF32 dscp (011100)—decimal value 28

AF33 dscp (011110)—decimal value 30

AF41 dscp (100010)—decimal value 34

AF42 dscp (100100)—decimal value 36

AF43 dscp (100110)—decimal value 38

cs1

CS1 (precedence 1) dscp (001000)—decimal value
8

cs2

CS2 (precedence 2) dscp (010000)—decimal value
16

cs3

CS3 (precedence 3) dscp (011000)—decimal value
24

cs4

CS4 (precedence 4) dscp (100000)—decimal value
32

cs5

CS5 (precedence 5) dscp (101000)—decimal value
40

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Configuring Classification

Configuring Protocol Classification

List of DSCP ValuesValue

cs6

cs7

default

ef

Procedure

Step 1

Step 2

Step 3

switch(config)# class-map type qos

class-name

switch(config-cmap-qos)# match
dscp dscp-list

CS6 (precedence 6) dscp (110000)—decimal value
48

CS7 (precedence 7) dscp (111000)—decimal value
56

Default dscp (000000)—decimal value 0

EF dscp (101110)—decimal value 46

PurposeCommand or Action

Enters global configuration mode.switch# configure terminal

Creates a named object that represents a class of traffic.
Class-map names can contain alphabetic, hyphen, or
underscore characters, are case sensitive, and can be up to
40 characters.

Configures the traffic class by matching packets based on
the values in the dscp-list variable. For a list of DSCP
values, see the Standard DSCP Values table.

Step 4

switch(config-cmap-qos)# no match
dscp dscp-list

This example shows how to classify traffic by matching packets based on the DSCP value in the DiffServ
field of the IP header:

switch# configure terminal
switch(config)# class-map type qos match-any class_dscp
switch(config-cmap-qos)# match dscp af21, af32

Use the show class-map command to display the DSCP class-map configuration:

switch# show class-map class_dscp

Configuring Protocol Classification

You can classify traffic based on the IPv4 Protocol field or the IPv6 Next Header field in the IP header. The
following table shows the protocol arguments:

(Optional)
Removes the match from the traffic class. For a list of
DSCP values, see the Standard DSCP Values table.

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Configuring IP RTP Classification

Table 5: Protocol Arguments

Configuring Classification

DescriptionArgument

Address Resolution Protocol (ARP)arp

CLNS End Systemsclns_es

CLNS Intermediate Systemclns_is

Dynamic Host Configuration (DHCP)dhcp

Label Distribution Protocol (LDP)ldp

NetBIOS Extended User Interface (NetBEUI)netbios

Procedure

PurposeCommand or Action

Step 1

Step 2

switch(config)# class-map type qos

class-name

Enters configuration mode.switch# configure terminal

Creates a named object that represents a class of
traffic. Class-map names can contain alphabetic,
hyphen, or underscore characters, are case
sensitive, and can be up to 40 characters.

Step 3

switch(config-cmap-qos)# match protocol
{arp | clns_es | clns_is | dhcp | ldp |

Configures the traffic class by matching packets
based on the specified protocol.

netbios}

Step 4

switch(config-cmap-qos)# no match
protocol {arp | clns_es | clns_is | dhcp | ldp

(Optional)
Removes the match from the traffic class.

| netbios}

This example shows how to classify traffic by matching packets based on the protocol field:

switch# configure terminal
switch(config)# class-map type qos class_protocol
switch(config-cmap-qos)# match protocol arp

Use the show class-map command to display the protocol class-map configuration:

switch# show class-map class_protocol

Configuring IP RTP Classification

The IP Real-time Transport Protocol (RTP) is a transport protocol for real-time applications that transmits
data such as audio or video and is defined by RFC 3550. Although RTP does not use a common TCP or UDP

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Configuring Classification

Configuring ACL Classification

port, you typically configure RTP to use ports 16384 to 32767. UDP communications use an even port and
the next higher odd port is used for RTP Control Protocol (RTCP) communications.

You can classify based on UDP port ranges, which are likely to target applications using RTP.

Procedure

PurposeCommand or Action

Step 1

Step 2

switch(config)# class-map type qos

class-name

Enters global configuration mode.switch# configure terminal

Creates a named object that represents a class of traffic.
Class-map names can contain alphabetic, hyphen, or
underscore characters, are case sensitive, and can be up
to 40 characters.

Step 3

switch(config-cmap-qos)# match ip
rtp port-number

Configures the traffic class by matching packets based
on a range of lower and upper UDP port numbers, which
is likely to target applications using RTP. Values can
range from 2000 to 65535.

Step 4

switch(config-cmap-qos)# no match
ip rtp port-number

(Optional)
Removes the match from the traffic class.

The following example shows how to classify traffic by matching packets based on UDP port ranges that are
typically used by RTP applications:

switch# configure terminal
switch(config)# class-map type qos match-any class_rtp
switch(config-cmap-qos)# match ip rtp 2000-2100, 4000-4100

Use the show class-map command to display the RTP class-map configuration:

switch# show class-map class_rtp

Configuring ACL Classification

You can classify traffic by matching packets based on an existing access control list (ACL). Traffic is classified
by the criteria defined in the ACL. The permit and deny ACL keywords are ignored in the matching; even
if a match criteria in the access-list has a deny action, it is still used for matching for this class.

Procedure

PurposeCommand or Action

Step 1

Step 2

switch(config)# class-map type qos

class-name

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Enters global configuration mode.switch# configure terminal

Creates a named object that represents a class of traffic.
Class-map names can contain alphabetic, hyphen, or
underscore characters, are case sensitive, and can be up to
40 characters.

Verifying the Classification Configuration

Configuring Classification

PurposeCommand or Action

Step 3

switch(config-cmap-qos)# match
access-group name acl-name

Configures a traffic class by matching packets based on
the acl-name. The permit and deny ACL keywords are
ignored in the matching.

Note

You can only define a single ACL in a class map.

You cannot add any other match criteria to a class
with a match access-group defined.

Step 4

switch(config-cmap-qos)# no match
access-group name acl-name

(Optional)
Removes the match from the traffic class.

This example shows how to classify traffic by matching packets based on existing ACLs:

switch# configure terminal
switch(config)# class-map type qos class_acl
switch(config-cmap-qos)# match access-group name acl-01

Use the show class-map command to display the ACL class-map configuration:

switch# show class-map class_acl

Verifying the Classification Configuration

Use one of the following commands to verify the configuration:

show policy-map [name]

running-config ipqos

startup-config ipqos

PurposeCommand

Displays the class maps defined on the switch.show class-map

Displays the policy maps defined on the switch.
Optionally, you can display the named policy only.

Displays information about the running configuration
for QoS.

Displays information about the startup configuration
for QoS.

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