QoS Modular QoS Command-Line Interface Configuration Guide Cisco IOS XE Release 3S
Applying QoS Features Using the MQC
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Applying QoS Features Using the MQC

Contents

Applying QoS Features Using the MQC

This module contains the concepts about applying QoS features using the Modular Quality of Service (QoS) Command-Line Interface (CLI) (MQC) and the tasks for configuring the MQC. The MQC allows you to define a traffic class, create a traffic policy (policy map), and attach the traffic policy to an interface. The traffic policy contains the QoS feature that will be applied to the traffic class.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Restrictions for Applying QoS Features Using the MQC

The MQC-based QoS does not support classification of legacy Layer 2 protocol packets such as Internetwork Packet Exchange (IPX), DECnet, or AppleTalk. When these types of packets are being forwarded through a generic Layer 2 tunneling mechanism, the packets can be handled by MQC but without protocol classification. As a result, legacy protocol traffic in a Layer 2 tunnel is matched only by a "match any" class or class-default.

The number of QoS policy maps and class maps supported varies by platform and release. See the following tables for the supported platform information.


Note


The policy map limitations do not refer to the number of applied policy map instances, only to the definition of the policy maps.


The following restrictions apply to Cisco IOS XE Release 3.5S for the Cisco ASR 903 router:
  • QoS policy maps are not supported in sessions.
  • Nested traffic maps are not supported.

For more information on restrictions for Cisco ASR 903 router, refer the Quality of Service Configuration Guidelines for Cisco ASR 903 Router.

Table 1 Cisco ASR 903 Policy and Class Map Support
 

Cisco IOS XE 3.5S, 3.6S, 3.7S, 3.8S

Cisco IOS XE 3.9S and higher

Number of unique policy-maps

1024

1024

Number of unique class-maps

4096

4096

Number of classes per policy-map

512

4096

Number of filters per class-map

16

16

Table 2 Cisco ASR 1000 Series Policy and Class Map Support
 

Cisco IOS XE 2.0S, 2.1S, 2.2S

Cisco IOS XE 2.3S

Cisco IOS XE 3.5S, 3.6S, 3.7S, 3.8S, 3.9S

Cisco IOS XE 3.10S and higher

Number of unique policy-maps

1024

4096

4096

4096

16000 (RP2, ESP40, ESP100, ESP200 models only)

Number of unique class-maps

4096

4096

4096

4096

Number of classes per policy-map

8

256

1000

1000

Number of filters per class-map

16

16

32

32

Table 3 Cisco CSR 1000V Policy and Class Map Support
 

Cisco IOS XE 3.9S and higher

Number of unique policy-maps

30

Number of unique class-maps

256

Number of classes per policy-map

32

Number of filters per class-map

8

Table 4 Cisco ISR 4451-X Policy and Class Map Support
 

Cisco IOS XE 3.9S and higher

Number of unique policy-maps

4000

Number of unique class-maps

4096

Number of classes per policy-map

256

Number of filters per class-map

32

Information About Applying QoS Features Using the MQC

The MQC Structure

The MQC structure allows you to define a traffic class, create a traffic policy, and attach the traffic policy to an interface.

The MQC structure consists of the following three high-level steps:

  1. Define a traffic class by using the class-map command. A traffic class is used to classify traffic.
  2. Create a traffic policy by using the policy-map command. (The terms traffic policy and policy map are often synonymous.) A traffic policy (policy map) contains a traffic class and one or more QoS features that will be applied to the traffic class. The QoS features in the traffic policy determine how to treat the classified traffic.
  3. Attach the traffic policy (policy map) to the interface by using the service-policy command.

Elements of a Traffic Class

A traffic class contains three major elements: a traffic class name, a series of match commands, and, if more than one match command is used in the traffic class, instructions on how to evaluate these match commands.

The match commands are used for classifying packets. Packets are checked to determine whether they meet the criteria specified in the matchcommands; if a packet meets the specified criteria, that packet is considered a member of the class. Packets that fail to meet the matching criteria are classified as members of the default traffic class.

Available match Commands

The table below lists some of the available match commands that can be used with the MQC. The available match commands vary by Cisco IOS XE release. For more information about the commands and command syntax, see the Cisco IOS Quality of Service Solutions Command Reference.

Table 5 match Commands That Can Be Used with the MQC

Command

Purpose

match access-group

Configures the match criteria for a class map on the basis of the specified access control list (ACL).

match any

Configures the match criteria for a class map to be successful match criteria for all packets.

match cos

Matches a packet based on a Layer 2 class of service (CoS) marking.

match destination-address mac

Uses the destination MAC address as a match criterion.

match discard-class

Matches packets of a certain discard class.

match [ip] dscp

Identifies a specific IP differentiated service code point (DSCP) value as a match criterion. Up to eight DSCP values can be included in one match statement.

match fr-dlci

Specifies the Frame Relay data-link connection identifier (DLCI) number as a match criterion in a class map.

match input-interface

Configures a class map to use the specified input interface as a match criterion.

match ip rtp

Configures a class map to use the Real-Time Transport Protocol (RTP) port as the match criterion.

match mpls experimental

Configures a class map to use the specified value of the Multiprotocol Label Switching (MPLS) experimental (EXP) field as a match criterion.

match mpls experimental topmost

Matches the MPLS EXP value in the topmost label.

match not

Specifies the single match criterion value to use as an unsuccessful match criterion.

Note   

The match not command, rather than identifying the specific match parameter to use as a match criterion, is used to specify a match criterion that prevents a packet from being classified as a member of the class. For instance, if the match not qos-group 6 command is issued while you configure the traffic class, QoS group 6 becomes the only QoS group value that is not considered a successful match criterion. All other QoS group values would be successful match criteria.

match packet length

Specifies the Layer 3 packet length in the IP header as a match criterion in a class map.

match port-type

Matches traffic on the basis of the port type for a class map.

match [ip] precedence

Identifies IP precedence values as match criteria.

match protocol

Configures the match criteria for a class map on the basis of the specified protocol.

Note   

A separate match protocol (NBAR) command is used to configure network-based application recognition (NBAR) to match traffic by a protocol type known to NBAR.

match protocol fasttrack

Configures NBAR to match FastTrack peer-to-peer traffic.

match protocol gnutella

Configures NBAR to match Gnutella peer-to-peer traffic.

match protocol http

Configures NBAR to match Hypertext Transfer Protocol (HTTP) traffic by URL, host, Multipurpose Internet Mail Extension (MIME) type, or fields in HTTP packet headers.

match protocol rtp

Configures NBAR to match RTP traffic.

match qos-group

Identifies a specific QoS group value as a match criterion.

match source-address mac

Uses the source MAC address as a match criterion.

Multiple match Commands in One Traffic Class

If the traffic class contains more than one match command, you need to specify how to evaluate the match commands. You specify this by using either the match-any or match-all keyword of the class-map command. Note the following points about the match-any and match-all keywords:

  • If you specify the match-any keyword, the traffic being evaluated by the traffic class must match one of the specified criteria.
  • If you specify the match-all keyword, the traffic being evaluated by the traffic class must match all of the specified criteria.
  • If you do not specify either keyword, the traffic being evaluated by the traffic class must match all of the specified criteria (that is, the behavior of the match-all keyword is used).

Elements of a Traffic Policy

A traffic policy contains three elements: a traffic policy name, a traffic class (specified with the class command), and the command used to enable the QoS feature.

The traffic policy (policy map) applies the enabled QoS feature to the traffic class once you attach the policy map to the interface (by using the service-policy command).


Note


A packet can match only one traffic class within a traffic policy. If a packet matches more than one traffic class in the traffic policy, the first traffic class defined in the policy will be used.


Commands Used to Enable QoS Features

The commands used to enable QoS features vary by Cisco IOS XE release. The table below lists some of the available commands and the QoS features that they enable. For complete command syntax, see the Cisco IOS QoS Command Reference.

For more information about a specific QoS feature that you want to enable, see the appropriate module of the Cisco IOS XE Quality of Service Solutions Configuration Guide.

Table 6 Commands Used to Enable QoS Features

Command

Purpose

bandwidth

Configures a minimum bandwidth guarantee for a class.

bandwidth remaining

Configures an excess weight for a class.

fair-queue

Enables the flow-based queueing feature within a traffic class.

drop

Discards the packets in the specified traffic class.

police

Configures traffic policing.

police (percent)

Configures traffic policing on the basis of a percentage of bandwidth available on an interface.

police (two rates)

Configures traffic policing using two rates, the committed information rate (CIR) and the peak information rate (PIR).

priority

Gives priority to a class of traffic belonging to a policy map.

queue-limit

Specifies or modifies the maximum number of packets the queue can hold for a class configured in a policy map.

random-detect

Enables Weighted Random Early Detection (WRED).

random-detect discard-class

Configures the WRED parameters for a discard-class value for a class in a policy map.

random-detect discard-class-based

Configures WRED on the basis of the discard class value of a packet.

random-detect exponential-weighting-constant

Configures the exponential weight factor for the average queue size calculation for the queue reserved for a class.

random-detect precedence

Configure the WRED parameters for a particular IP Precedence for a class policy in a policy map.

service-policy

Specifies the name of a traffic policy used as a matching criterion (for nesting traffic policies [hierarchical traffic policies] within one another).

set atm-clp

Sets the cell loss priority (CLP) bit when a policy map is configured.

set cos

Sets the Layer 2 class of service (CoS) value of an outgoing packet.

set discard-class

Marks a packet with a discard-class value.

set [ip] dscp

Marks a packet by setting the differentiated services code point (DSCP) value in the type of service (ToS) byte.

set fr-de

Changes the discard eligible (DE) bit setting in the address field of a Frame Relay frame to 1 for all traffic leaving an interface.

set mpls experimental

Designates the value to which the MPLS bits are set if the packets match the specified policy map.

set precedence

Sets the precedence value in the packet header.

set qos-group

Sets a QoS group identifier (ID) that can be used later to classify packets.

shape

Shapes traffic to the indicated bit rate according to the algorithm specified.

Nested Traffic Classes

The MQC does not necessarily require that you associate only one traffic class to one traffic policy. When packets meet more than one match criterion, multiple traffic classes can be associated with a single traffic policy.

Similarly, the MQC allows multiple traffic classes (nested traffic classes, which are also called nested class maps or MQC Hierarchical class maps) to be configured as a single traffic class. This nesting can be achieved with the use of the match class-map command. The only method of combining match-any and match-all characteristics within a single traffic class is with the match class-map command.

match-all and match-any Keywords of the class-map Command

One of the commands used when you create a traffic class is the class-mapcommand. The command syntax for the class-map command includes two keywords: match-all and match-any. The match-all and match-any keywords need to be specified only if more than one match criterion is configured in the traffic class. Note the following points about these keywords:

  • The match-all keyword is used when all of the match criteria in the traffic class must be met in order for a packet to be placed in the specified traffic class.
  • The match-any keyword is used when only one of the match criterion in the traffic class must be met in order for a packet to be placed in the specified traffic class.
  • If neither the match-all keyword nor match-any keyword is specified, the traffic class will behave in a manner consistent with the match-all keyword.

input and output Keywords of the service-policy Command

As a general rule, the QoS features configured in the traffic policy can be applied to packets entering the interface or to packets leaving the interface. Therefore, when you use the service-policy command, you need to specify the direction of the traffic policy by using the input or output keyword.

For instance, the service-policy output policy-map1 command would apply the QoS features in the traffic policy to the interface in the output direction. All packets leaving the interface (output) are evaluated according to the criteria specified in the traffic policy named policy-map1.


Note


For Cisco IOS XE Release 2.1 and later releases, queueing mechanisms are not supported in the input direction. Nonqueueing mechanisms (such as traffic policing and traffic marking) are supported in the input direction. Also, classifying traffic on the basis of the source MAC address (using the match source-address mac command) is supported in the input direction only.


Benefits of Applying QoS Features Using the MQC

The MQC structure allows you to create the traffic policy (policy map) once and then apply it to as many traffic classes as needed. You can also attach the traffic policies to as many interfaces as needed.

How to Apply QoS Features Using the MQC

Creating a Traffic Class

To create a traffic class, use the class-map command to specify the traffic class name. Then use one or more match commands to specify the appropriate match criteria. Packets matching the criteria that you specify are placed in the traffic class. For more information about the match-all and match-any keywords of the class-map comand, see the “match-all and match-any Keywords of the class-map Command” section.


Note


The match cos command is shown in Step 4. The match cos command is simply an example of one of the match commands that you can use. For information about the other available match commands, see the “match-all and match-any Keywords of the class-map Command” section.


SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    class-map [match-all | match-any] class-map-name

    4.    match cos cos-number

    5.    Enter additional match commands, if applicable; otherwise, continue with step 6.

    6.    end


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Router> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 configure terminal


    Example:
    Router# configure terminal
     

    Enters global configuration mode.

     
    Step 3 class-map [match-all | match-any] class-map-name


    Example:
    Router(config)# class-map match-any class1
     

    Creates a class to be used with a class map and enters class-map configuration mode.

    • The class map is used for matching packets to the specified class.
    • Enter the class name.
    Note   

    The match-all keyword specifies that all match criteria must be met. The match-any keyword specifies that one of the match criterion must be met. Use these keywords only if you will be specifying more than one match command.

     
    Step 4 match cos cos-number


    Example:
    Router(config-cmap)# match cos 2
     

    Matches a packet on the basis of a Layer 2 class of service (CoS) number.

    • Enter the CoS number.
    Note   

    The match cos command is an example of the match commands you can use. For information about the other match commands that are available, see the “match-all and match-any Keywords of the class-map Command” section.

     
    Step 5 Enter additional match commands, if applicable; otherwise, continue with step 6.  

    --

     
    Step 6 end


    Example:
    Router(config-cmap)# end
     

    (Optional) Exits QoS class-map configuration mode and returns to privileged EXEC mode.

     

    Creating a Traffic Policy


    Note


    The bandwidth command is shown in Step 5. The bandwidth command is an example of the commands that you can use in a policy map to enable a QoS feature (in this case, Class-based Weighted Fair Queuing (CBWFQ). For information about other available commands, see the “Elements of a Traffic Policy” section.


    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    policy-map policy-map-name

      4.    class {class-name | class-default}

      5.    bandwidth {bandwidth-kbps | percent percent}

      6.    Enter the commands for any additional QoS feature that you want to enable, if applicable; otherwise, continue with Step 7.

      7.    end


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Router> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.
       
      Step 2 configure terminal


      Example:
      Router# configure terminal
       

      Enters global configuration mode.

       
      Step 3 policy-map policy-map-name


      Example:
      Router(config)# policy-map policy1
       

      Creates or specifies the name of the traffic policy and enters QoS policy-map configuration mode.

      • Enter the policy map name.
       
      Step 4 class {class-name | class-default}


      Example:
      Router(config-pmap)# class class1 
       

      Specifies the name of a traffic class and enters QoS policy-map class configuration mode.

      Note   

      This step associates the traffic class with the traffic policy.

       
      Step 5 bandwidth {bandwidth-kbps | percent percent}


      Example:
      Router(config-pmap-c)# bandwidth 3000 
       

      (Optional) Specifies a minimum bandwidth guarantee to a traffic class in periods of congestion.

      • A minimum bandwidth guarantee can be specified in kb/s or by a percentage of the overall available bandwidth.
      Note   

      The bandwidth command enables CBWFQ. The bandwidth command is an example of the commands that you can use in a policy map to enable a QoS feature. For information about the other commands available, see the “Elements of a Traffic Policy” section.

       
      Step 6 Enter the commands for any additional QoS feature that you want to enable, if applicable; otherwise, continue with Step 7.  

      --

       
      Step 7 end


      Example:
      Router(config-pmap-c)# end
       

      (Optional) Exits QoS policy-map class configuration mode and returns to privileged EXEC mode.

       

      Attaching a Traffic Policy to an Interface Using the MQC


      Note




      Note


      Cisco IOS XE Release 2.3.0 and later releases do not support the attachment of policies for ATM interfaces that have unspecified bit rate (UBR) configured as the default mode on their VC or virtual path (VP). An attempt to use this configuration results in an error message: CBWFQ: Not supported on ATM interfaces with UBR configuration. You can also specify UBR with a rate in the UBR configuration, if you do not want to use the default UBR value.


      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    interface type number

        4.    service-policy {input | output} policy-map-name

        5.    end


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Router> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.
         
        Step 2 configure terminal


        Example:
        Router# configure terminal
         

        Enters global configuration mode.

         
        Step 3 interface type number


        Example:
        Router(config)# interface serial 0/0/1
         

        Configures an interface type and enters interface configuration mode.

        • Enter the interface type and interface number.
         
        Step 4 service-policy {input | output} policy-map-name


        Example:
        Router(config-if)# service-policy input policy1 
         

        Attaches a policy map to an interface.

        • Enter either the input or output keyword and the policy map name.
         
        Step 5 end


        Example:
        Router(config-if)# end
         

        (Optional) Exits interface configuration mode and returns to privileged EXEC mode.

         

        Verifying the Traffic Class and Traffic Policy Information

        The show commands described in this section are optional and can be entered in any order.

        SUMMARY STEPS

          1.    enable

          2.    show class-map

          3.    show policy-map policy-map-name class class-name

          4.    show policy-map

          5.    show policy-map interface type number

          6.    exit


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Router> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.
           
          Step 2 show class-map


          Example:
          Router# show class-map
           
          
           

          (Optional) Displays all class maps and their matching criteria.

           
          Step 3 show policy-map policy-map-name class class-name


          Example:
          Router#
           
          show policy-map policy1 class class1
           

          (Optional) Displays the configuration for the specified class of the specified policy map.

          • Enter the policy map name and the class name.
           
          Step 4 show policy-map


          Example:
          Router# show policy-map
           

          (Optional) Displays the configuration of all classes for all existing policy maps.

           
          Step 5 show policy-map interface type number


          Example:
          Router# show policy-map interface serial 0/0/1
           

          (Optional) Displays the statistics and the configurations of the input and output policies that are attached to an interface.

          • Enter the interface type and number.
           
          Step 6 exit


          Example:
          Router# exit
           

          (Optional) Exits privileged EXEC mode.

           

          Configuration Examples for Applying QoS Features Using the MQC

          Example: Creating a Traffic Class

          In the following example, two traffic classes are created and their match criteria are defined. For the first traffic class called class1, access control list (ACL) 101 is used as the match criterion. For the second traffic class called class2, ACL 102 is used as the match criterion. Packets are checked against the contents of these ACLs to determine if they belong to the class.

          Router(config)# class-map class1
          Router(config-cmap)# match access-group 101
          Router(config-cmap)# exit
          Router(config)# class-map class2
          Router(config-cmap)# match access-group 102
          Router(config-cmap)# end
          

          Example Creating a Traffic Policy

          In the following example, a traffic policy called policy1 is defined. The traffic policy contains the QoS features to be applied to two classes--class1 and class2. The match criteria for these classes were previously defined (as described in the Example Creating a Traffic Class).

          For class1, the policy includes a bandwidth allocation request and a maximum packet count limit for the queue reserved for the class. For class2, the policy specifies only a bandwidth allocation request.

          Router(config)# policy-map policy1
          Router(config-pmap)# class class1
          Router(config-pmap-c)# bandwidth 3000
          Router(config-pmap-c)# queue-limit 30
          Router(config-pmap-c)# exit
          Router(config-pmap)# class class2
          Router(config-pmap-c)# bandwidth 2000
          Router(config-pmap-c)# end
          

          Example: Attaching a Traffic Policy to an Interface

          The following example shows how to attach an existing traffic policy to an interface. After you define a traffic policy with the policy-map command, you can attach it to one or more interfaces by using the service-policy command in interface configuration mode. Although you can assign the same traffic policy to multiple interfaces, each interface can have only one traffic policy attached in the input direction and only one traffic policy attached in the output direction.

          Router(config)# interface fastethernet 1/1/1
          Router(config-if)# service-policy output policy1
          Router(config-if)# exit
          Router(config)# interface fastethernet 1/0/0
          Router(config-if)# service-policy output policy1
          Router(config-if)# end
          

          Example: match not Command

          The match notcommand is used to specify a specific QoS policy value that is not used as a match criterion. If the match not command is issued, all other values of that QoS policy become successful match criteria. For instance, if the match not qos-group 4 command is issued in QoS class-map configuration mode, the specified class will accept all QoS group values except 4 as successful match criteria.

          In the following traffic class, all protocols except IP are considered successful match criteria:

          Router(config)# class-map noip
          Router(config-cmap)# match not protocol ip
          Router(config-cmap)# end
          

          Example: Default Traffic Class Configuration

          Unclassified traffic (traffic that does not meet the match criteria specified in the traffic classes) is treated as belonging to the default traffic class.

          If you do not configure a default class, packets are still treated as members of the default class. However, by default, the default class has no QoS features enabled. Therefore, packets belonging to a default class have no QoS functionality. These packets are placed into a first-in, first-out (FIFO) queue managed by tail drop. Tail drop is a means of avoiding congestion that treats all traffic equally and does not differentiate between classes of service. Queues fill during periods of congestion. When the output queue is full and tail drop is in effect, packets are dropped until the congestion is eliminated and the queue is no longer full.

          Example: class-map match-any and class-map match-all Commands

          This example illustrates the difference between the class-map match-any command and the class-map match-all command. The match-any and match-all keywords determine how packets are evaluated when multiple match criteria exist. Packets must either meet all of the match criteria (match-all) or meet one of the match criteria (match-any) to be considered a member of the traffic class.

          The following example shows a traffic class configured with the class-map match-all command:

          If a packet arrives on a router with the traffic class called cisco1 configured on the interface, the packet is evaluated to determine if it matches the IP protocol, QoS group 4, and access group 101. If all three of these match criteria are met, the packet is classified as a member of the traffic class cisco1.

          The following example shows a traffic class that is configured with the class-map match-any command:

          In the traffic class called cisco2, the match criteria are evaluated consecutively until a successful match criterion is located. The packet is first evaluated to determine whether the IP protocol can be used as a match criterion. If the IP protocol can be used as a match criterion, the packet is matched to traffic class cisco2. If the IP protocol is not a successful match criterion, then QoS group 4 is evaluated as a match criterion. Each criterion is evaluated to see if the packet matches that criterion. Once a successful match occurs, the packet is classified as a member of traffic class cisco2. If the packet matches none of the specified criteria, the packet is classified as a member of the default traffic class (class default-class).

          Note that the class-map match-all command requires that all of the match criteria be met in order for the packet to be considered a member of the specified traffic class (a logical AND operator). In the first example, protocol IP AND QoS group 4 AND access group 101 must be successful match criteria. However, only one match criterion must be met in order for the packet in the class-map match-any command to be classified as a member of the traffic class (a logical OR operator). In the second example, protocol IP OR QoS group 4 OR access group 101 must be successful match criterion.

          Example: Traffic Class as a Match Criterion (Nested Traffic Classes)

          There are two reasons to use the match class-map command. One reason is maintenance; if a large traffic class currently exists, using the traffic class match criterion is easier than retyping the same traffic class configuration. The more common reason for the match class-map command is to allow users to use match-any and match-all statements in the same traffic class. If you want to combine match-all and match-any characteristics in a traffic policy, create a traffic class using one match criterion evaluation instruction (either match-any or match-all) and then use this traffic class as a match criterion in a traffic class that uses a different match criterion type.

          Here is a possible scenario: Suppose A, B, C, and D were all separate match criterion, and you wanted traffic matching A, B, or C and D (A or B or [C and D]) to be classified as belonging to the traffic class. Without the nested traffic class, traffic would either have to match all four of the match criterion (A and B and C and D) or match any of the match criterion (A or B or C or D) to be considered part of the traffic class. You would not be able to combine “and” (match-all) and “or” (match-any) statements within the traffic class, and you would therefore be unable to configure the desired configuration.

          The solution: Create one traffic class using match-all for C and D (which we will call criterion E), and then create a new match-any traffic class using A, B, and E. The new traffic class would have the correct evaluation sequence (A or B or E, which would also be A or B or [C and D]). The desired traffic class configuration has been achieved.

          The only method of mixing match-all and match-any statements in a traffic class is through the use of the traffic class match criterion.

          Example: Nested Traffic Class for Maintenance

          In the following example, the traffic class called class1 has the same characteristics as the traffic class called class2, with the exception that traffic class class1 has added a destination address as a match criterion. Rather than configuring traffic class class1 line by line, you can enter the match class-map class2 command. This command allows all of the characteristics in the traffic class called class2 to be included in the traffic class called class1, and you can add the new destination address match criterion without reconfiguring the entire traffic class.

          Router(config)# class-map match-any class2
          Router(config-cmap)# match protocol ip
          Router(config-cmap)# match qos-group 3
          Router(config-cmap)# match access-group 2
          Router(config-cmap)# exit
          Router(config)# class-map match-all class1
          Router(config-cmap)# match class-map class2
          Router(config-cmap)# match destination-address mac 00.00.00.00.00.00 
          Router(config-cmap)# exit
          

          Example: Nested Traffic Class to Combine match-any and match-all Characteristics in One Traffic Class

          The only method of including both match-any and match-all characteristics in a single traffic class is to use the match class-map command. To combine match-any and match-all characteristics into a single class, use the match-any instruction to create a traffic class that uses a class configured with the match-all instruction as a match criterion (through the match class-map command).

          The following example shows how to combine the characteristics of two traffic classes, one with match-any and one with match-all characteristics, into one traffic class with the match class-map command. The result requires a packet to match one of the following three match criteria to be considered a member of traffic class class4: IP protocol and QoS group 4, destination MAC address 00.00.00.00.00.00, or access group 2.

          In this example, only the traffic class called class4 is used with the traffic policy called policy1.

          Router(config)# class-map match-all class3
          Router(config-cmap)# match protocol ip
          Router(config-cmap)# match qos-group 4
          Router(config-cmap)# exit
          Router(config)# class-map match-any class4
          Router(config-cmap)# match class-map class3
          Router(config-cmap)# match destination-address mac 00.00.00.00.00.00 
          Router(config-cmap)# match access-group 2
          Router(config-cmap)# exit
          Router(config)# policy-map policy1
          Router(config-pmap)# class class4
          Router(config-pmap-c)# police 8100 1500 2504 conform-action transmit exceed-action set-qos-transmit 4
          Router(config-pmap-c)# end
          

          Example: Traffic Policy as a QoS Policy (Hierarchical Traffic Policies)

          A traffic policy can be included in a QoS policy when the service-policy command is used in QoS policy-map class configuration mode. A traffic policy that contains a traffic policy is called a hierarchical traffic policy.

          A hierarchical traffic policy contains a child policy and a parent policy. The child policy is the previously defined traffic policy that is being associated with the new traffic policy through the use of the service-policy command. The new traffic policy using the preexisting traffic policy is the parent policy. In the example in this section, the traffic policy called child is the child policy and traffic policy called parent is the parent policy.

          Hierarchical traffic policies can be attached to subinterfaces and ATM PVCs. When hierarchical traffic policies are used, a single traffic policy (with a child and a parent policy) can be used to shape and prioritize permanent virtual connection (PVC) traffic. In the following example, the child policy is responsible for prioritizing traffic and the parent policy is responsible for shaping traffic. In this configuration, the parent policy allows packets to be sent from the interface, and the child policy determines the order in which the packets are sent.

          Router(config)# policy-map child
          Router(config-pmap)# class voice
          Router(config-pmap-c)# priority 50
          Router(config)# policy-map parent
          Router(config-pmap)# class class-default
          Router(config-pmap-c)# shape average 10000000
          Router(config-pmap-c)# service-policy child

          The value used with the shape command is provisioned from the committed information rate (CIR) value from the service provider.

          Additional References

          Related Documents

          Related Topic

          Document Title

          Cisco IOS commands

          Cisco IOS Master Commands List, All Releases

          QoS commands: complete command syntax, command modes, command history, defaults, usage guidelines, and examples

          Cisco IOS Quality of Service Solutions Command Reference

          Packet classification

          “Classifying Network Traffic” module

          Frame Relay Fragmentation (FRF) PVCs

          “FRF .20 Support” module

          Selective Packet Discard

          “IPv6 Selective Packet Discard” module

          Scaling and performance information

          “Broadband Scalability and Performance” module of the Cisco ASR 1000 Series Aggregation Services Routers Software Configuration Guide.

          Technical Assistance

          Description

          Link

          The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

          http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

          Feature Information for Applying QoS Features Using the MQC

          The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

          Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

          Table 7 Feature Information for Applying QoS Features Using the MQC

          Feature Name

          Releases

          Feature Information

          Class-Based Weighted Fair Queueing (CBWFQ)

          Cisco IOS XE Release 2.1

          Cisco IOS XE Release 3.5S

          This feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers.

          In Cisco IOS XE Release 3.5S, support was added for the Cisco ASR 903 Router.

          Modular QoS CLI (MQC)

          Cisco IOS XE Release 2.1

          Cisco IOS XE Release 3.5S

          This module describes how to apply and configure quality of service (QoS) features using the modular QoS CLI (MQC). The MQC allows you to define a traffic class, create a traffic policy (policy map), and attach the traffic policy to an interface. The traffic policy contains the QoS feature that will be applied to the traffic class.

          This feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers.

          This feature was enhanced to provide infrastructure support for additional features included with Cisco IOS XE Release 2.3.

          In Cisco IOS XE Release 3.5S, support was added for the Cisco ASR 903 router.

          MQC Hierarchical Class Map

          Cisco IOS XE Release 3.2

          MQC allows multiple traffic classes (nested traffic classes, which are also called nested class maps or MQC hierarchical class maps) to be configured as a single traffic class. This feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers.

          Priority Queueing

          Cisco IOS XE Release 2.1

          This feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers.

          Weighted Random Early Detection

          Cisco IOS XE Release 2.1

          This feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers.