Cisco ASR 9000 Series Aggregation Services Router Modular Quality of Service Command Reference, Release 4.2.x
Congestion Avoidance Commands
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Congestion Avoidance Commands

Congestion Avoidance Commands

This chapter describes commands used to avoid congestion.

Congestion avoidance is achieved through packet dropping. Cisco IOS XR software supports the following quality of service (QoS) congestion avoidance techniques that drop packets:

•Random early detection (RED

•Weighted random early detection (WRED)

•Tail drop

For detailed information about congestion avoidance concepts, configuration tasks and examples, see the Configuring Congestion Avoidance module in the Cisco ASR 9000 Series Aggregation Services Router Modular Quality of Service Configuration Guide

bandwidth (QoS)

To specify the minimum bandwidth allocated to a class belonging to a policy map, use the bandwidth command in policy map class configuration mode. To remove the bandwidth specified for a class, use the no form of this command.

bandwidth { rate [units] | percent percentage-value }

no bandwidth { rate [units] | percent percentage-value }

Syntax Description

rate

Minimum bandwidth, in the units specified, to be assigned to the class. Range is from 1 to 4294967295.

units

Specifies the units for the bandwidth. Values can be:

  • bps—bits per second
  • gbps—gigabits per second
  • kbps—kilobits per second (default)
  • mbps—megabits per second

percent percentage-value

Specifies the amount of guaranteed bandwidth, based on an absolute percentage of available bandwidth. Range is from 1 to 100.

Command Default

The default units is kbps.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

You must be in a user group associated with a task group that includes the proper task IDs. The command reference guides include the task IDs required for each command. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The bandwidth command is used to specify the minimum guaranteed bandwidth allocated for traffic matching a particular class. Bandwidth may be defined as a specific value or may be set as a percentage of the interface bandwidth.

If a percentage value is set, the accuracy that can be expected is 1 percent.


Note


The bandwidth value takes into account the Layer 2 encapsulation that is applied to traffic leaving the interface. For Ethernet , the encapsulation is considered to be 14 bytes; whereas for IEEE 802.1Q, the encapsulation is 18 bytes. The actual bandwidth assigned to a class can be seen in the output of the show qos interface command.


Be careful when specifying bandwidth guarantees close to 100 percent, because the Layer 2 encapsulation considered does not include the entire Layer 2 header. This can lead to oversubscription, particularly in the case of small packet sizes.

A policy map can have a single bandwidth statement per class. Both percentage and actual value bandwidth configurations can be used within a policy map.

The bandwidth command does not specify how the bandwidth is to be shared. Instead it specifies how much bandwidth is guaranteed per class, by setting the number of tokens that are assigned to the token bucket of a particular class. For configured behavior to work correctly, you must ensure that the sum of the bandwidths plus any priority traffic is not greater than the bandwidth of the interface itself. If the interface is oversubscribed, unpredictable behavior results.

The bandwidth of the interface is set to be that of the physical interface, unless a hierarchical policy is defined that reduces the bandwidth available to the traffic. The following example shows a hierarchical policy being used to shape traffic to the specified value. The child policy then determines how the shaped bandwidth should be apportioned between the specified classes:

policy-map parent
  class match_all
  shape average 1000000
  bandwidth 1000000
    service-policy child

policy-map child
  class gold
    bandwidth percent 20
  class silver
    bandwidth percent 40
  class default
    bandwidth percent 40

Note


The bandwidth command is part of the parent policy. In this instance, the bandwidth command not only sets the minimum bandwidth for the class but also resets the reference point for the bandwidth percent statements in the child policy.


  • If bandwidth is configured in the parent class, parent minimum bandwidth is used as a reference for the child bandwidth percentages.
  • If bandwidth is not configured in the parent class, the implicit minimum bandwidth, which is a portion of the total unallocated bandwidth allocated to the class based on the explicit or implicit bandwidth remaining, is used as a reference.

For subinterface policies:

  • If bandwidth is configured in the parent class, parent minimum bandwidth is used as a reference for child bandwidth percentages.
  • If bandwidth remaining is configured in the parent class, bandwidth-remaining-percent * interface-rate is used as a reference.
  • If bandwidth is not configured in the parent class, shape rate is used as a reference.

In the following example, the hierarchical policy is attached to the main interface, and the parent classes are a mix of bandwidth and shape only classes:

policy-map hqos
 class c1
   bandwidth percent 40
    service-policy child
 class c2
   shape average 500000000
    service-policy child

The reference for the child policy in class c2 is the implicit bandwidth of class c2 bounded by the shape rate of class c2. Therefore, the reference = (60 percent * interface bandwidth) / 3 bounded by 500000000 kbps.

In the following example, the hierarchical policy is a class-default only parent shape configured on subinterfaces:

policy-map sub_int_hqos
 class c1ass-default
   shape average 40
    service-policy child

The class-default parent shape rate is used as reference.

When the percent keyword is used with the bandwidth command, the bandwidth of the interface is defined as being the Layer 2 capacity excluding the Gigabit Ethernet or POS encapsulation but including the High-Level Data Link Control (HDLC) flags, frame check sequence (FCS), and so on. These have to be included because they are applied per packet, and the system cannot predict how many packets of a particular packet size are being sent out.

For example, the following policy is applied to an OC-192 interface:

policy-map oc-192
  class c1
  bandwidth percent 50

The resulting bandwidth reservation for class c1 is 4,792,320 kbps. This equates to 50 percent of the OC-192 bandwidth excluding the GE or POS overhead.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to guarantee 50 percent of the interface bandwidth to a class called class1 and 10 percent of the interface bandwidth to a class called class2:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth percent 50
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# class class2
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth percent 10

Related Commands

Command

Description

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

class-map

Defines a traffic class and the associated rules that match packets to the class.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

queue-limit

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

random-detect precedence

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a particular IP precedence.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

show qos interface

Displays QoS information for a specific interface.  

bandwidth remaining

To specify how to allocate leftover bandwidth to various classes, use the bandwidth remaining command in policy map class configuration mode. To return to the system defaults, use the no form of this command.

bandwidth remaining [ percent percentage-value | ratio ratio-value ]

no bandwidth remaining [ percent percentage-value | ratio ratio-value ]

Syntax Description

percent percentage-value

Specifies the amount of guaranteed bandwidth, based on an absolute percentage of the available bandwidth. Range is from 1 to 100.

ratio ratio-value

Specifies the amount of guaranteed bandwidth, based on a bandwidth ratio value. Range is 1 to 1020.

Command Default

No bandwidth is specified.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

You must be in a user group associated with a task group that includes the proper task IDs. The command reference guides include the task IDs required for each command. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The bandwidth remaining command is used to set the Modified Deficit Round Robin (MDRR) weight for the particular class.

When applied within an egress service policy, the command is used to define how any unallocated bandwidth should be apportioned. It is typically used in conjunction with the bandwidth configuration at the parent level in hierarchical policy maps. In such a combination, if the minimum bandwidth guarantees are met, the remaining bandwidth is shared in the ratio defined by the bandwidth remaining command in the class configuration in the policy map.

The available bandwidth is equally distributed among those queueing classes that do not have the remaining bandwidth explicitly configured.


Note


On egress, the actual bandwidth of the interface is determined to be the Layer 2 capacity excluding CRC. These have to be included because they are applied per packet, and the system cannot predict how many packets of a particular packet size are being sent out.


The bandwidth remaining command is used to proportionally allocate bandwidth to the particular classes, but there is no reserved bandwidth capacity.

On both ingress and egress, if the bandwidth remaining command is not present, then the bandwidth is shared equally among the configured queueing classes present in the policy-map. When attempting precise calculations of expected MDRR behavior, you must bear in mind that because you are dealing with the bandwidth remaining on the link, you must convert the values to the bandwidth remaining percentages on the link, based upon the packet sizes of the traffic within the class. If the packet sizes are the same in all the classes, then the defined ratio is enforced precisely and predictably on the link.

Task ID

Task ID

Operations

qos

read, write

Examples

RP/0/RSP0/CPU0:router(config)#policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth percent 50
RP/0/RSP0/CPU0:router(config-pmap-c)#bandwidth remaining percent 20
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)#class class2
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth percent 10
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth remaining percent 80
  

In the following example, remaining bandwidth is shared by classes class1 and class2 in a 20:80 ratio.

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth remaining percent 20
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# class class2
RP/0/RSP0/CPU0:router(config-pmap-c)# bandwidth remaining percent 80
  

child-conform-aware

To prevent the parent policer from dropping any ingress traffic that conforms to the maximum rate specified in the child policer, use the child-conform-aware command in policy map police configuration mode. To remove this action from the policy map, use the no form of this command.

child-conform-aware

no child-conform-aware

Syntax Description

This command has no keywords or arguments.

Command Default

The child-conform-aware command is not configured.

Command Modes

Policy map police configuration

Command History

Release

Modification

Release 4.0.0

This command was introduced.

Usage Guidelines

You must be in a user group associated with a task group that includes the proper task IDs. The command reference guides include the task IDs required for each command. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

In hierarchical policing, traffic is policed first at the child policer level and then at the parent policer level. It is possible for traffic that conforms to the maximum rate specified by the child policer to be dropped by the parent policer.

In enhanced hierarchical ingress policing, the child-conform-aware command prevents the parent policer from dropping any ingress traffic that conforms to the maximum rate specified in the child policer.

Task ID

Task ID

Operations

qos

read, write

Examples

This example shows parent and child policy maps in which two classes are defined in the child policy. In class AF1, the exceed action is set to an action other than to drop traffic.

If the child-conform-aware command were not configured in the parent policy, the parent policer would drop traffic that matches the conform rate of the child policer but exceeds the conform rate of the parent policer.

The child-conform-aware command prevents the parent policer from dropping any ingress traffic that conforms to the maximum rate specified in the child policer.

This example shows parent and child policies in which two classes are defined in the child policy. In class AF1, the exceed action is set to an action other than to drop traffic.

If the child-conform-aware command were not configured in the parent policy, the parent policer would drop traffic that matches the conform rate of the child policer but exceeds the conform rate of the parent policer.

When used in the parent policer, the child-conform-aware command prevents the parent policer from dropping any ingress traffic that conforms to the committed rate specified in the child policer.

In this example, class EF in the child policy is configured with a committed rate of 1 Mbps, a conform action and an exceed action. The traffic that is below 1 Mbps is presented to the parent policer with the MPLS EXP bit set to 4, and traffic that exceeds 1 Mbps is dropped.

Class AF1 in the child policy is configured with a committed rate of 1 Mbps, a conform action and an exceed action. The traffic that is below 1 Mbps is presented to the parent policer with the MPLS EXP bit set to 3, and traffic that exceeds 1 Mbps is presented to the parent policer with the MPLS EXP bit set to 2.

With this child policy configuration, the parent policer sees traffic from the child classes as exceeding its committed rate of 2 Mbps. Without the child-conform-aware command in the parent policer, the parent polices to 2 Mbps, which can result into dropping some conformed traffic from class EF in the child policy. When the child-conform-aware command is configured in the parent policer, the parent policer does not drop any traffic that conforms under the child policy.

RP/0/RSP0/CPU0:router(config)# policy-map parent
RP/0/RSP0/CPU0:router(config-pmap)# class class-default
RP/0/RSP0/CPU0:router(config-pmap-c)# service-policy child
RP/0/RSP0/CPU0:router(config-pmap-c)# police rate 2 mbps
RP/0/RSP0/CPU0:router(config-pmap-c-police)# child-conform-aware
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action transmit
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exceed-action drop

RP/0/RSP0/CPU0:router(config)# policy-map child
RP/0/RSP0/CPU0:router(config-pmap)# class EF
RP/0/RSP0/CPU0:router(config-pmap-c)# police rate 1 mbps
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set mpls experimental imposition 4
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exceed-action drop
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exit
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# class AF1
RP/0/RSP0/CPU0:router(config-pmap-c)# police rate 1 mbps
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set mpls experimental imposition 3
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set mpls experimental imposition 2

Related Commands

Command

Description

exceed-action

Configures the action to take on packets that exceed the rate limit.  

police rate

Configures traffic policing and enters policy map police configuration mode.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

compress header ip

To enable IP header compression for a policy map class, use the compress header ip command in policy map class configuration mode. To disable header compression, use the no form of this command.

compress header ip

no compress header ip

Syntax Description

This command has no keywords or arguments.

Command Default

By default, IP header compression is disabled.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 4.0.0

This command was introduced.

Usage Guidelines

You must be in a user group associated with a task group that includes the proper task IDs. The command reference guides include the task IDs required for each command. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to enable IP header compression for a policy map class:

RP/0/RSP0/CPU0:router(config)#class-map class1
RP/0/RSP0/CPU0:router(config-cmap)# match access-group ipv4 customer1
RP/0/RSP0/CPU0:router(config-cmap)# exit
RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# compress header ip
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# exit

Related Commands

Command

Description

class-map

Defines a traffic class and the associated rules that match packets to the class.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

service-policy (interface)

Attachs a policy map to an input interface or output interface to be used as the service policy for that interface.  

conform-action

To configure the action to take on packets that conform to the rate limit, use the conform-action command in policy map police configuration mode. To remove a conform action from the policy-map, use the no form of this command.

conform-action [ drop | set options | transmit ]

no conform-action [ drop | set options | transmit ]

Syntax Description

drop

(Optional) Drops the packet.

set options

(Optional) Configures the specified packet properties. Replace options with one of the following keywords or keyword arguments:

  • atm-clp value —Sets the cell loss priority (CLP) bit.
  • cos value —Sets the class of service value. Range is 0 to7.
  • cos [inner]value —Sets the class of service value. Range is 0 to 7.
  • dei—Sets the drop eligible indicator (DEI). Can be 0 or 1.
  • discard-class value —Sets the discard class value. Range is 0 to 7.
  • dscp value —Sets the differentiated services code point (DSCP) value and sends the packet. See Table 1 for a list of valid values.
  • dscp [tunnel] value —Sets the differentiated services code point (DSCP) value and sends the packet. See Table 1 for a list of valid values. With the tunnel keyword, the DSCP is set in the outer header.
  • mpls experimental {topmost | imposition} value —Sets the experimental (EXP) value of the Multiprotocol Label Switching (MPLS) packet topmost label or imposed label. Range is 0 to 7.
  • precedence precedence —Sets the IP precedence and sends the packet See Table 2 for a list of valid values.
  • precedence [tunnel] precedence —Sets the IP precedence and sends the packet. See Table 1 for a list of valid values. With the tunnel keyword, the precedence is set in the outer header.
  • qos-group value —Sets the QoS group value.
  • srp-priority value —Sets the Spatial Reuse Protocol (SRP) priority. Range is 0 to 7.

transmit

(Optional) Transmits the packets.

Command Default

By default, if no action is configured on a packet that conforms to the rate limit, the packet is transmitted.

Command Modes

Policy map police configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.0.0

The set dei keyword was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

For more information regarding the traffic policing feature, see the police rate command.

  • experimental, qos-group, and discard class values, or
  • experimental and qos-group values, or
  • experimental and discard class values

The set dei action in policy maps is supported on 802.1ad packets for:

  • Ingress and egress
  • Layer 2 subinterfaces
  • Layer 2 main interfaces
  • Layer 3 main interfaces

Note


The set DEI action is ignored for traffic on interfaces that are not configured for 802.1ad encapsulation.


Task ID

Task ID

Operations

qos

read, write

Examples

In the following example for MPLS, traffic policing is configured to set the MPLS experimental bit for packets that conform to the rate limit:

RP/0/RSP0/CPU0:router(config)# class-map class
RP/0/RSP0/CPU0:router(config-cmap)# match mpls experimental topmost 0
RP/0/RSP0/CPU0:router(config-cmap)# exit

RP/0/RSP0/CPU0:router(config)# policy-map child
RP/0/RSP0/CPU0:router(config-pmap)# class prec1
RP/0/RSP0/CPU0:router(config-pmap-c)# police rate 100000000 peak-rate 3125000 peak-burst 3125000 
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set mpls experimental imp 1
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set qos-group 1
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exit
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# exit

RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/1/0/9
RP/0/RSP0/CPU0:router(config-if) service-policy input policy1

In this example, the police rate is set to 5 Mbps. Conforming traffic is marked with a DEI value of 0; traffic that exceeds the police rate is marked with a DEI value of 1.

RP/0/RSP0/CPU0:router(config)# policy-map 1ad-mark-dei
RP/0/RSP0/CPU0:router(config-pmap)# class c1
RP/0/RSP0/CPU0:router(config-pmap-c)# police rate 5 mbps
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set dei 0
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exceed-action set dei 1
RP/0/RSP0/CPU0:router(config-pmap-c-police)# end-policy-map

Related Commands

Command

Description

child-conform-aware

Prevents the parent policer from dropping any ingress traffic that conforms to the maximum rate specified in the child policer.  

conform-color

(Used for SIP 700 cards only.) Configures preclassification of ingress Layer 2 Frame Relay packets that have been previously marked as not discard eligible on an upstream node. These previously-marked packets are analyzed and preclassified by the color-aware policer on the ingress interface as part of the 2-rate 3-color (2R3C) traffic policing feature.  

exceed-action

Configures the action to take on packets that exceed the rate limit.  

police rate

Configures traffic policing and enters policy map police configuration mode.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

violate-action

Configures the action to take on packets that violate the rate limit.  

conform-color

To configure preclassification of Frame Relay packets that are not discard-eligible, use the conform-color command in policy map police configuration mode. To remove a conform color from the policy-map, use the no form of this command.

conform-color class-map-name

no conform-color class-map-name

Syntax Description

class-map-name

Specifies the class-map to associate with the conform-color.

Command Default

By default, if no preclassification is configured for a packet, the packet is not analyzed by the color-aware policer on the ingress interface, and the packet is given regular policing treatment.

Command Modes

Policy map police configuration

Command History

Release

Modification

Release 4.1.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Typically, frame relay packets from a previous node are marked by default as fr-de = 0 (meaning not discard eligible) or fr-de = 1 (meaning discard eligible). For non-discard-eligible treatment, you must create a class map for the fr-de=0 case and assign the conform-color to that class-map.

For more information regarding the traffic policing feature, see the police rate command.


Note


The multi-action policer sets cannot be used for IP packets.


Task ID

Task ID

Operations

qos

read, write

Examples

In this example, conform-color is configured for preclassification of packets that are not discard-eligible.

RP/0/RSP0/CPU0:routerconfigure
RP/0/RSP0/CPU0:router(config)# class-map match-all match_not_frde
RP/0/RSP0/CPU0:router(config-cmap)# match not fr-de 1
RP/0/RSP0/CPU0:router(config-cmap)# policy-map 2R3C_conform_example
RP/0/RSP0/CPU0:router(config-pmap)# class class-default
RP/0/RSP0/CPU0:router(config-pmap-c)#  police rate 768000 burst 288000 peak-rate 1536000 peak-burst 576000
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-color match_not_frde
RP/0/RSP0/CPU0:router(config-pmap-c-police)# conform-action set qos-group 1
RP/0/RSP0/CPU0:router(config-pmap-c-police)# exit
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# exit
RP/0/RSP0/CPU0:router(config)# interface pos 0/2/0/1
RP/0/RSP0/CPU0:router(config-if) service-policy input policy1

Related Commands

Command

Description

child-conform-aware

Prevents the parent policer from dropping any ingress traffic that conforms to the maximum rate specified in the child policer.  

class-map

Defines a traffic class and the associated rules that match packets to the class.  

conform-action

Configures the action to take on packets that conform to the rate limit.  

exceed-action

Configures the action to take on packets that exceed the rate limit.  

exceed-color

(Used for SIP 700 cards only.) Configures preclassification of ingress Layer 2 Frame Relay packets that have been previously marked as discard eligible on an upstream node. These previously-marked packets are analyzed and preclassified by the color-aware policer on the ingress interface as part of the 2-rate 3-color (2R3C) traffic policing feature.  

match fr-de

Match packets on the basis of the Frame Relay discard eligibility (DE) bit setting.  

police rate

Configures traffic policing and enters policy map police configuration mode.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

violate-action

Configures the action to take on packets that violate the rate limit.  

queue-limit

To specify or modify the maximum number of packets the queue can hold for a class policy configured in a policy map, use the queue-limit command in policy map class configuration mode. To remove the queue packet limit from a class, use the no form of this command.

queue-limit value [unit]

no queue-limit

Syntax Description

value

Maximum threshold for tail drop in bytes. Range is from 1 to 4294967295.

unit

(Optional) Units for the queue limit value. Values can be:

  • bytes —bytes
  • kbytes —kilobytes
  • mbytes —megabytes
  • ms —milliseconds
  • packets —packets (default)
  • us —microseconds
Note   

When the specified units is packets, packets are assumed to be 256 bytes in size.

Command Default

100 milliseconds: maximum threshold for tail drop

10 milliseconds: maximum threshold for high-priority queues

Maximum threshold units are in packets.


Note


The default queue limit is 100 ms of the “service rate” for a given queue class.


Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Packets satisfying the match criteria for a class accumulate in the queue reserved for the class until they are serviced by the scheduling mechanism. The queue-limit command defines the maximum threshold for a class. When that threshold is reached, enqueued packets to the class queue result in tail drop (packet drop). Tail drop is a congestion avoidance technique that drops packets when an output queue is full, until congestion is eliminated.

Use the show qos interface command to display the queue limit and other policer values.

Queue Limit Default Values

The following default values are used when queue-limit is not configured in the class:

  • If QoS is not configured:
    • The queue limit is 100 ms at the interface rate.
  • If QoS is configured and Weighted Random Early Detection (WRED) is not configured:
    • Queue limit is 100 ms at the guaranteed service rate of the queue for non-priority queues.
    • Queue limit is 10 ms at the interface rate for Level 1 priority classes.
    • Queue limit is 10 ms at parent guaranteed service rate for Level 2 priority classes.
  • If QoS is configured and WRED is configured:
    • Queue limit is two times the WRED maximum threshold. The maximum threshold can be an explicitly configured value or an implicit 100 ms.
    • If more than one WRED profile is configured in the class, the maximum threshold is the maximum for all profiles.
    • When the queue-limit is configured in time units, the guaranteed service rate is used to compute the queue limit.

When the queue limit is configured in time units, the guaranteed service rate of the class is used to calculate the queue limit in bytes. For example: time_unit in ms * guaranteed_service_rate in kbps / 8 is equivalent to queue-limit in bytes.

The following restrictions apply to queue limits:

  • Queue limit should be at least the maximum MTU size, which is 9 * 1024 bytes = 9kb.
  • Queue limit cannot exceed 1 GB, which is the maximum packet buffer size in ingress and egress queuing ASICs.
  • Only time-based units are allowed on bundle targets.

Guaranteed Service Rate

The guaranteed service rate is defined as the service rate of the queue when all queues are backlogged and derived as:

minimum_bandwidth + (bandwidth_remaining_percent * unallocated_bandwidth)

The following example shows the guaranteed service rate calculation:

policy-map sample_policy
  class c1
    bandwidth percent 30
    bandwidth remaining percent 40
  class c2
    bandwidth percent 20
  class class-default
  

guaranteed service rate of c1 = 30 percent LR + (40 percent * 50 percent * LR)

guaranteed service rate of c2 = 20 percent LR + (30 percent * 50 percent * LR)

guaranteed service rate of class-default = 30 percent * 50 percent * LR

  • Where LR is line rate of the target on which service policy "sample_policy" is attached.
  • 50 percent is unallocated bandwidth.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to set the queue limit for a class to 1000000 packets for policy map policy1:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# queue-limit 1000000
  

Related Commands

Command

Description

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

show qos interface

Displays QoS information for a specific interface.  

random-detect

To enable random early detection (RED), use the random-detect command in policy map class configuration mode. To remove RED, use the no form of this command.

random-detect { cos value | default | dei value | discard-class value | dscp value | exp value | precedence value | min-threshold [units] max-threshold [units] }

no random-detect [ cos value | default | dei value | discard-class value | dscp value | exp value | precedence value | min-threshold [units] max-threshold [units] ]

Syntax Description

cos value

COS-based WRED.

default

Enables RED with default minimum and maximum thresholds.

dei value

Discard-eligibility indicator based WRED. Can be 0 or 1.

discard-class value

Discard-class based WRED.

dscp value

DSCP-based WRED.

exp value

MPLS Experimental-based WRED.

precedence value

Precedence-based WRED. Values can be:

  • 0 or routine
  • 1 or priority
  • 2 or immediate
  • 3 or flash
  • 4 or flash-override
  • 5 or critical
  • 6 or internet
  • 7 or network

min-threshold

Minimum threshold in number of packets. The value range of this argument is from 0 to 1073741823 in bytes.

max-threshold

Maximum threshold the units specified. The value range of this argument is from the value of the min-threshold argument or 23, whichever is larger, to 1073741823. When the average queue length exceeds the maximum threshold, RED drops all packets with the specified discard class value.

units

(Optional) Units for the threshold values. Values can be:

  • bytes—bytes
  • gbytes—gigabytes
  • kbytes—kilobytes
  • mbytes —megabytes
  • ms —milliseconds
  • packets —packets (default)
  • us —microseconds

Command Default

Default unit for max-threshold and min-threshold is packets .

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.0.0

The dei keyword was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The RED congestion avoidance technique takes advantage of the congestion control mechanism of TCP. By randomly dropping packets before periods of high congestion, RED tells the packet source to decrease its transmission rate. Assuming the packet source is using TCP, it decreases its transmission rate until all the packets reach their destination, indicating that the congestion is cleared. You can use RED as a way to cause TCP to slow transmission of packets. TCP not only pauses, but it also restarts quickly and adapts its transmission rate to the rate that the network can support.

RED distributes losses in time and maintains normally low queue depth while absorbing traffic bursts. When enabled on an interface, RED begins dropping packets when congestion occurs at a rate you select during configuration.

When time units are used, the guaranteed service rate is used to compute thresholds.

The default value for RED is calculated as follows:

B = 1/2 default max-threshold, based on 100 ms

where B is the bandwidth for the queue. When all the queues are congested, the bandwidth for the queue is equal to the guaranteed service rate of the queue.

The mark probability is always set to 1.

When the value of the units argument is packets, packets are assumed to be 256 bytes in size.

Weighted Random Early Detection

The following restrictions apply to Weighted Random Early Detection (WRED):

  • For thresholds in time units, the guaranteed service rate is used to calculate the thresholds in bytes.
  • Default RED minimum threshold—50 ms at the guaranteed service rate.
  • Default RED maximum threshold—100 ms as the guaranteed service rate.

For bundles, queue limit and WRED thresholds are supported in time units only.


Note


RED is enabled when you configure any of the supported random-detect commands.


Random early detection based on the DEI value is supported on 802.1ad packets for:

  • Ingress and egress
  • Layer 2 subinterfaces
  • Layer 2 main interfaces
  • Layer 3 main interfaces

Note


If there are any marking actions in the policy, the marked values are used for doing WRED.


Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to enable RED using a minimum threshold value of 1000000 and a maximum threshold value of 2000000:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect 1000000 2000000
  

In this example, congestion is managed by dropping packets with a DEI value of 1 before dropping packets with a DEI value of 0.

RP/0/RSP0/CPU0:router(config)# policy-map dei-sample
RP/0/RSP0/CPU0:router(config-pmap)# class class-default
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect dei 1 1000 6000
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect dei 0 5000 10000
RP/0/RSP0/CPU0:router(config-pmap-c)# end-policy-map
  

Related Commands

Command

Description

random-detect precedence

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a particular IP precedence.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

random-detect cos

To configure Weighted Random Early Detection (WRED) thresholds for packets with a specific class of service (CoS) value, use the random-detect cos command in policy map class configuration mode. To return the thresholds to the default for the CoS, use the no form of this command.

random-detect cos cos-value min-threshold [units] max-threshold [units]

no random-detect cos cos-value min-threshold [units] max-threshold [units]

Syntax Description

cos-value

CoS value. Valid values are from 0 to 7. Up to eight values can be entered separated by commas.

min-threshold

Minimum threshold in number of packets. The value range of this argument is from 0 to 1073741823 in bytes.

max-threshold

Maximum threshold in number of packets. The value range of this argument is from the value of the min-threshold argument to 1073741823.

units

(Optional) Units for the threshold values. Values can be:

  • bytes —bytes
  • gbytes —gigabytes
  • kbytes —kilobytes
  • mbytes —megabytes
  • ms —milliseconds
  • packets —packets (default)
  • us —microseconds

Command Default

Default unit for max-threshold and min-threshold is packets.

min-threshold: 30 ms

max-threshold: 100 ms

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The random-detect cos command is allowed in a service policy attached to a Layer 2 VPN attachment circuit or physical Ethernet interface only. (The command in invalid in a policy attached to a Layer 3 interface.)


Note


Only time-based units are allowed on bundle targets.


When the value of the units argument is packets, packets are assumed to be 256 bytes in size.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to configure CoS:

RP/0/RSP0/CPU0:router(config)# policy-map map1
RP/0/RSP0/CPU0:router(config-pmap)# class c 
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect cos 3 1000 bytes 2000 bytes
  

Related Commands

Command

Description

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

show qos interface

Displays QoS information for a specific interface.  

random-detect dscp

To configure the Weighted Random Early Detection (WRED) thresholds for packets with a specific differentiated services code point (DSCP) value, use the random-detect dscp command in policy map class configuration mode. To return the thresholds to the default for the DSCP value, use the no form of this command.

random-detect dscp dscp-value min-threshold [units] max-threshold [units]

no random-detect dscp dscp-value min-threshold [units] max-threshold [units]

Syntax Description

dscp-value

DSCP value. Up to eight dscp-values (any combination of numbers, ranges, and reserved keywords) can be used separated by commas. The following arguments are supported:

  • Number from 0 to 63 that sets the DSCP value.
  • Range of DSCP values. Range is from 0 to 63.
  • Reserved keywords can be specified instead of numeric values. Table 1 describes the reserved keywords.

min-threshold

Minimum threshold in number of packets. The value range of this argument is from 0 to 1073741823. When the average queue length reaches the minimum threshold, WRED randomly drops some packets with the specified DSCP value.

max-threshold

Maximum threshold in number of packets. The value range of this argument is from the value of the min-threshold argument to 1073741823. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified DSCP value.

units

(Optional) Units for the threshold values. Values can be:

  • bytes—bytes
  • gbytes—gigabytes
  • kbytes—kilobytes
  • mbytes—megabytes
  • ms—milliseconds
  • packets—packets (default)
  • us—microseconds

Command Default

Match packets with default DSCP (000000).

Default unit for max-threshold and min-threshold is packets.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion exists. WRED is most useful with protocols like TCP that respond to dropped packets by decreasing the transmission rate.

Reserved keywords can be specified instead of numeric values. See Table 1 for the list of keywords.

When the value of the units argument is packets, packets are assumed to be 256 bytes in size.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows that for packets with DSCP AF11, the WRED minimum threshold is 1,000,000 bytes and the maximum threshold is 2,000,000 bytes:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect dscp AF11 1000000 2000000

Related Commands

Command

Description

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

random-detect precedence

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a particular IP precedence.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

random-detect exp

To configure the Weighted Random Early Detection (WRED) thresholds for packets marked with a specific MPLS experimental (EXP) bit value, use the random-detect exp command in policy map class configuration mode. To return the value to the default, use the no form of this command.

random-detect exp exp-value min-threshold [units] max-threshold [units]

no random-detect exp exp-value min-threshold [units] max-threshold [units]

Syntax Description

exp-value

MPLS experimental value. Valid values are from 0 to 7. Up to eight values can be entered separated by commas.

min-threshold

Minimum threshold in number of packets. The value range of this argument is from 0 to 1073741823 in bytes.

max-threshold

Maximum threshold in units specified. The value range of this argument is from the value of the min-threshold argument to 1073741823. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified experimental value.

units

(Optional) Units for the threshold values. Values can be:

  • bytes—bytes
  • gbytes—gigabytes
  • kbytes—kilobytes
  • mbytes—megabytes
  • ms—milliseconds
  • packets—packets (default)
  • us—microseconds

Command Default

Default unit for max-threshold and min-threshold is packets .

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion exists. WRED is most useful with protocols like TCP that respond to dropped packets by decreasing the transmission rate.

When the value of the units argument is packets, packets are assumed to be 256 bytes in size.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows that for Multiprotocol Label Switching (MPLS) packets with an EXP field value of 4, the WRED minimum threshold is 1,000,000 bytes and the maximum threshold is 2,000,000 bytes:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# random-detect exp 4 1000000 20000

Related Commands

Command

Description

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

random-detect dscp

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a specific differentiated services code point (DSCP) value.  

random-detect precedence

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a particular IP precedence.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

random-detect precedence

To configure the Weighted Random Early Detection (WRED) thresholds for packets with a particular IP precedence, use the random-detect precedence command in policy map class configuration mode. To return the thresholds to the default for the precedence, use the no form of this command.

random-detect precedence precedence-value min-threshold [units] max-threshold [units]

no random-detect precedence precedence-value min-threshold [units] max-threshold [units]

Syntax Description

precedence-value

An IP precedence value identifier that specifies the exact value. Range is from 0 to 7. Reserved keywords can be specified instead of numeric values. Table 1 describes the reserved keywords. Up to eight values or reserved keywords can be entered separated by commas.

min-threshold

Minimum threshold in number of packets. Range is from 0 to 1073741823 in bytes.

max-threshold

Maximum threshold in the units specified. Range is from the value of the min-threshold argument to 1073741823. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified precedence value.

units

(Optional) Units for the threshold values. Values can be:

  • bytes—bytes
  • gbytes—gigabytes
  • kbytes—kilobytes
  • mbytes—megabytes
  • ms—milliseconds
  • packets—packets (default)
  • us—microseconds

Command Default

Default unit for max-threshold and min-threshold is packets.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion exists. WRED is most useful with protocols like TCP that respond to dropped packets by decreasing the transmission rate.

When you configure the random-detect command on an interface, packets are given preferential treatment based on the IP precedence of the packet. Use the random-detect precedence command to adjust the treatment for different precedences.

When the value of the units argument is packets, packets are assumed to be 256 bytes in size.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows that for packets with precedence 3, the WRED minimum threshold is 1,000,000 bytes and maximum threshold is 2,000,000 bytes:

RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)#random-detect precedence 3 1000000 2000000
  

Related Commands

Command

Description

bandwidth (QoS)

Specifies the minimum bandwidth allocated to a class belonging to a policy map.  

class (policy-map)

Specifies the name of the class whose policy you want to create or change.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

random-detect dscp

Configures the Weighted Random Early Detection (WRED) thresholds for packets with a specific differentiated services code point (DSCP) value.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

service-policy (policy map class)

To use a service policy as a QoS policy within a policy map (called a hierarchical service policy), use the service-policy command in policy map class configuration mode. To disable a particular service policy as a QoS policy within a policy map, use the no form of this command.

service-policy [ type qos ] policy-map-name

no service-policy [ type qos ] policy-map-name

Syntax Description

type qos

(Optional) Specifies a QoS service policy.

policy-map-name

Name of the predefined policy map to be used as a QoS policy. The name can be a maximum of 40 alphanumeric characters.

Command Default

No service policy is specified.

Type is QoS when not specified.

Command Modes

Policy map class configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The service-policy (policy-map class) command creates hierarchical service policies in policy-map class configuration mode.

This command is different from the service-policy (interface) command used in interface configuration mode.

The child policy is the previously defined service policy that is being associated with the class default of the parent policy-map. The new service policy using the preexisting service policy is the parent policy.

The service-policy (policy-map class) command has the following restrictions:

  • The priority command can be used only in the child policy.
  • If the bandwidth command is used in the child policy, the bandwidth command must also be used in the parent policy. The one exception is for policies using the default class.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows how to create a hierarchical service policy in the service policy called parent:

RP/0/RSP0/CPU0:router(config)# policy-map child
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# priority
RP/0/RSP0/CPU0:router(config-pmap-c)# exit
RP/0/RSP0/CPU0:router(config-pmap)# exit
RP/0/RSP0/CPU0:router(config)# policy-map parent
RP/0/RSP0/CPU0:router(config-pmap)# class class-default
RP/0/RSP0/CPU0:router(config-pmap-c)# shape average 10000000
RP/0/RSP0/CPU0:router(config-pmap-c)# service-policy child

Related Commands

Command

Description

bandwidth (QoS)

Specifies the minimum bandwidth allocated to a class belonging to a policy map.  

class-map

Defines a traffic class and the associated rules that match packets to the class.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

priority (QoS)

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

service-policy (interface)

Attachs a policy map to an input interface or output interface to be used as the service policy for that interface.  

service-policy (interface)

To attach a policy map to an input interface or output interface to be used as the service policy for that interface, and optionally multiple subinterfaces, use the service-policy command in the appropriate configuration mode. To remove a service policy from an input or output interface, use the no form of the command.

service-policy { input | output } policy-map [ shared-policy-instance instance-name ]

no service-policy { input | output } policy-map [ shared-policy-instance instance-name ]

Syntax Description

input

Attaches the specified policy map to the input interface.

output

Attaches the specified policy map to the output interface.

policy-map

Name of a service policy map (created using the policy-map command) to be attached.

shared-policy-instance

(Optional) Allows sharing of QoS resources across multiple subinterfaces.

Note   

Sharing across multiple physical interfaces is not supported.

instance-name

(Optional) String of up to 32 characters to identify the shared policy instance.

Command Default

No service policy is specified.

Command Modes

Interface configuration

Layer 2 transport configuration

Subinterface configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 3.9.0

This command was updated to support shared policy instance over bundle interfaces.

Release 3.6.0

The command was supported in Layer 2 transport configuration mode.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

You can attach a single policy map to one or more interfaces to specify the service policy for those interfaces. The class policies composing the policy map are then applied to packets that satisfy the class map match criteria for the class. To apply a new policy to an interface, you must remove the previous policy. A new policy cannot replace an existing policy.

Task ID

Task ID

Operations

qos

read, write

Examples

The following example shows policy map policy1 applied to Packet-over-SONET/SDH (POS) interface 0/2/0/0:

RP/0/RSP0/CPU0:router(config)# class-map class1
RP/0/RSP0/CPU0:router(config-cmap)# match precedence ipv4 1
RP/0/RSP0/CPU0:router(config-cmap)# exit
RP/0/RSP0/CPU0:router(config)# policy-map policy1
RP/0/RSP0/CPU0:router(config-pmap)# class class1
RP/0/RSP0/CPU0:router(config-pmap-c)# set precedence 2
RP/0/RSP0/CPU0:router(config-pmap)# exit
RP/0/RSP0/CPU0:router(config)# interface pos 0/2/0/0
RP/0/RSP0/CPU0:router(config-if)# service-policy output policy1
  

The following example shows policy map policy2 applied to GigabitEthernet subinterface 0/1/0/0.1.

RP/0/RSP0/CPU0:router(config)# class-map class2
RP/0/RSP0/CPU0:router(config-cmap)# exit

RP/0/RSP0/CPU0:router(config)# policy-map policy2
RP/0/RSP0/CPU0:router(config-pmap)# class-map class2
RP/0/RSP0/CPU0:router(config-pmap-c)# set precedence 3
RP/0/RSP0/CPU0:router(config-pmap)# exit

RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/1/0/0.1
RP/0/RSP0/CPU0:router(config-subif)# service-policy input policy2 shared-policy-instance ethernet101
  

The following example shows policy map policy 1 applied to Bundle-Ether interfaces 100.1 and 100.2.

RP/0/RSP0/CPU0:router(config)# interface Bundle-Ether 100.1
RP/0/RSP0/CPU0:router(config-if)# service-policy policy1 shared-policy-instance subscriber1
RP/0/RSP0/CPU0:router(config-if)# exit

RP/0/RSP0/CPU0:router(config)# interface Bundle-Ether 100.2
RP/0/RSP0/CPU0:router(config-if)# service-policy output policy1 shared-policy-instance subscriber1
  

Related Commands

Command

Description

class-map

Defines a traffic class and the associated rules that match packets to the class.  

policy-map

Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.  

service-policy (policy map class)

Uses a service policy as a QoS policy within a policy map.  

show policy-map interface

Displays policy configuration information for all classes configured for all service policies on the specified interface.  

show policy-map shared-policy-instance

Displays the statistics for all details of the shared policy instance.  

show qos summary

To list the interfaces at a specific location, use the show qos summary command in EXEC mode.

show qos summary [ shared-policy-instance instance-name location rack/slot/module/interface.subinterface | police [ interface type instance | location [ rack/slot/module/interface.subinterface | location-name ] ] | policy policy-name [ interface type instance | location node-location ] | queue [ interface type instance | location node-location ] ]

Syntax Description

shared-policy-instance instance-name

String of up to 32 characters to identify the shared policy instance.

location rack/slot/module/ interface.subinterface

Location of node in format rack/slot/module/interface.subinterface.

police

Show policer interface statistics.

interface type instance

Interface type and number.

location location-name

String to identify the fully qualified location specification.

policy policy-name

String to identify the policy.

location node-location

Identifies fully qualified location specification.

queue

Show queue statistics.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Task ID

Task ID

Operations

qos

read, write

Examples

This example shows the results of the command to show interfaces at location 0/RSP0/CPU0 for a shared-policy-instance:

RP/0/RSP0/CPU0:router# show qos summary shared-policy-instance instancetwo location 0/RSP0/CPU0

list of interfaces retrieved
  TenGigE0/0/0.1
  TenGigE0/0/0.2
RP/0/RSP0/CPU0:router#
  

Related Commands

Command

Description

show policy-map shared-policy-instance

Displays the statistics for all details of the shared policy instance.  

show qos shared-policy-instance

Lists interface details for a specific location of a specific shared policy instance, attached to either an input or output interface.