Modular QoS Configuration Guide for Cisco NCS 540 Series Routers, Cisco IOS XR Release 7.10.x - Configuring Hierarchical Modular QoS [Cisco Network Convergence System 540 Series Routers] (2024)

Hierarchical QoS (H-QoS) is a QoS model that enables you to specify QoS behavior at multiple levels of hierarchy. This chapter provides information about this feature and the different steps involved in configuring it.

This chapter covers the following topics:

Overview of Hierarchical Modular QoS

Table 1. Feature History Table
Feature Name	Release Information	Feature Description
Scale Limits for H-QoS on Cisco NCS 540-24Q8L2DD-SYS Routers	Release 7.6.1	With this release, 750 egress interfaces and subinterfaces are available for configuring QoS policies in the H-QoS model on Cisco NCS 540-24Q8L2DD-SYS routers. You can now achieve higher egress policy-map scales because of the increased number of VOQs available per subinterface. In earlier releases, 250 egress interfaces and subinterfaces were available for configuring QoS policies in the H-QoS model.

Hierarchical QoS (H-QoS) allows you to specify QoS behavior at multiple policy levels, which provides a high degree of granularity in traffic management.

H-QoS is applied on the router interface using nested traffic policies. The first level of traffic policy, the parent traffic policy, is used for controlling the traffic at the main interface or sub-interface level. The second level of traffic policy, the child traffic policy, is used for more control over a specific traffic stream or class. The child traffic policy, is a previously defined traffic policy, that is referenced within the parent traffic policy using the service-policy command.

Two-level H-QoS is supported on both ingress and egress directions on all line cards and on physical or bundle main interfaces and sub-interfaces.

Three-level Hierarchical QoS (H-QoS) enables enforcement of class/service, group/ Ethernet Flow Point (EFP), and port level SLAs. You can apply regular two-level egress H-QoS policies on the sub-interfaces to achieve class and EFP SLAs at child and parent levels. In addition, you can apply a port shaper policy on the main interface to achieve an aggregated port level SLA in a 1+2 H-QoS or three-level H-QoS model.

An important point to note is that before Release 6.6.25 (where the three-level H-QoS capability was introduced), when you applied class-default shaper on a main interface, it was enforced only on the traffic going through the main interface. With three-level HQoS, a class default shaper that is applied on the main interface is considered as a port shaper and enforced on all traffic going out of that physical port. The advantage of three-level H-QoS is that the parent shaper on the sub-interfaces is allowed to oversubscribe, thus enabling best effort sharing of the aggregate port shaper at the third level.

Restrictions for Configuring H-QoS

The following restrictions are applicable while configuring H-QoS:

The parent traffic policy only supports the traffic class of type class-default.
The parent traffic policy only supports the class-action shape and no other queuing action can be configured in it.
While configuring on the router, it is mandatory that the priority class must have traffic shaper in the child traffic policy.
The sum of the bandwidth of the child policies must be less than the parent policy’s traffic shaper.
For congestion avoidance and management, the traffic shaper in the parent traffic policy calculates the queue limit and drop priority.
H-QoS profile and ingress peering profile don't work simultaneously. Hence, features requiring a peering profile also do not work with the H-QoS profile enabled.
PBTS feature does not work when the H-QoS profile is enabled. This is due to TCAM limitations.
A maximum of 896 bundle sub-interfaces are only supported in the system, even if there are no QoS policies applied. This is due to an internal LAG_ID resource consumption in HQoS profile mode for bundle sub-interfaces with or without QoS policies being applied.
A maximum of 4 priority levels are only supported in HQoS profile mode unlike the default mode where 7-priority levels are supported. The restriction also applies to physical and bundle main interface policies where 7-level priorities were previously used in non-H-QoS profile mode.
Bandwidth and Bandwidth remaining configurations are not supported simultaneously within the same policy-map. If a class has bandwidth (CIR), other classes must also have only bandwidth configuration. If a class-map has bandwidth remaining percent/ratio (EIR), other classes should also have only the bandwidth remaining configuration. Shaping is applied on any class.
In HQOS Mode, if multiple queues are configured with BRR and there is high congestion on the LP (Low Priority) queues then one queue with BRR gets more credits than rest of the LP queues. The deviation is proportional to the congestion in LP queues.
Priority classes must have rate limit configuration by using a Shaping configuration. The effective shaper value is taken as priority bandwidth reservation. Sum of priority bandwidth reservations across all sub-interfaces and main interfaces must not exceed the network interface (NIF) port speed. This is to avoid over-subscription of priority traffic across the network interface port.
See Also
Modular QoS Configuration Guide for Cisco NCS 540 Series Routers, Cisco IOS XR Release 7.11.x - QoS for Bridge-Group Virtual Interfaces [Cisco Network Convergence System 540 Series Routers]CISCO NCS 540 SERIES CONFIGURATION MANUAL Pdf Download Modular QoS Configuration Guide for Cisco NCS 540 Series Routers, Cisco IOS XR Release 7.4.x - Configuring Modular QoS Service Packet Classification [Cisco Network Convergence System 540 Series Routers]Converged SDN Transport Implementation Guide

Rates of non-priority classes and parent shaping can be over-subscribed.
The granularity of bandwidth or bandwidth remaining ration (BRR) is 1:64 as compared to 1:4096 in non-hqos mode. So, there could be accuracy differences in bandwidth performance based on the values used.
Filtering for egress IPv4 and IPv6 multicast traffic is not supported if H-QoS is configured on the router.

The following restrictions are applicable while configuring three-level H-QoS:

There is no support for bandwidth action at the EFP parent level. All EFP/sub-interface policies get a fair share of the port shaper.
Three-level H-QoS does not apply to ingress policies or to egress marking policies.
Executing clear qos counters on the main interface clears only the main interface policy statistics. Use the “all” option to clear all sub-interface statistics or alternately, clear the sub-interface policy statistics individually.
Main interface policy statistics do not reflect the sub-interface packet / byte counters, although the port shaper is enforced on all logical ports for a given physical interface. The sub-interface policy-map statistics reflect the transmitted and dropped packet/byte count post-port shaper enforcement.

Configuring Hierarchical Queuing

Before you configure H-QoS, you must enable the H-QoS profile on the router. After enabling H-QoS profile, reload the router, as shown in the following configuration.

adminhw-module location all reloadRouter# configureRouter(config)# hw-module profile qos hqos-enableRouter(config)# commitRouter# adminsysadmin-vm:0_RP0# hw-module location all reload

The steps that are involved in configuring hierarchical queuing are as follows:

Configure a class-map.
Configure a child traffic policy using the class-map that was configured in the previous step.
Configure a parent traffic policy and add the child traffic policy in it.

The parent traffic policy is the H-QoS traffic policy and it can be applied on physical or bundle main interfaces and sub-interfaces.

Configuration Example

Configuration of a class-map is as follows:

Router# configureRouter(config)# class-map match-any tc2Router(config-cmap)# match traffic-class 1Router(config-cmap)# end-class-mapRouter(config)# commit

Configuration of a child traffic policy is as follows:

Router# configureRouter(config)# policy-map childRouter(config-pmap)# class tc2Router(config-pmap-c)# shape average percent 20Router(config-pmap-c)# exitRouter(config-pmap)# class class-defaultRouter(config-pmap-c)# shape average percent 1Router(config-pmap)# end-policy-mapRouter(config)# commit

Configuration of a parent traffic policy is as follows:

Router# configureRouter(config)# policy-map parentRouter(config-pmap)# class class-defaultRouter(config-pmap-c)# service-policy childRouter(config-pmap-c)# shape average percent 50Router(config-pmap)# end-policy-mapRouter(config)# commit

Running Configuration

/* Configuration of a Class-map */class-map match-any tc2 match traffic-class 1 end-class-map!/* Configuration of a Child Traffic Policy */policy-map child class tc2 shape average percent 20 ! class class-default shape average percent 1 ! end-policy-map!/* Configuration of a Parent Traffic Policy */policy-map parent class class-default service-policy child shape average percent 50 ! end-policy-map!

Applying the Parent Traffic Policy on a Main Interface

Router# configureRouter(config)# Interface TenGigE 0/0/0/10Router(config-int)# service-policy output parentRouter(config-int)# commit

Applying the Parent Traffic Policy on a Sub-interface

Router# configureRouter(config)# Interface TenGigE 0/0/0/10.1Router(config-int)# service-policy output parentRouter(config-int)# commit

Verification

Verify if the H-QoS traffic policy is applied correctly on the interface using the commands show qos interface interface-name output . In the following example, the Level1 Class gives information about the class-map that is associated with the parent traffic policy and the Level2 Class gives information about the class-maps that are associated with the child traffic policy.

RP/0/RP0/CPU0:ios#show qos interface ten0/0/0/10 outputNOTE:- Configured values are displayed within parenthesesInterface TenGigE0/0/0/10 ifh 0x1e0 -- output policyNPU Id: 0Total number of classes: 3Interface Bandwidth: 10000000 kbpsVOQ Base: 1136Accounting Type: Layer1 (Include Layer 1 encapsulation and above)------------------------------------------------------------------------------Level1 Class = class-defaultQueue Max. BW. = no max (50 %)Queue Min. BW. = 0 kbps (default)Inverse Weight / Weight = 0 / (BWR not configured) Level2 Class = tc2 Egressq Queue ID = 1138 (LP queue) Queue Max. BW. = 1020015 kbps (20 %) Queue Min. BW. = 0 kbps (default) Inverse Weight / Weight = 1 / (BWR not configured) Guaranteed service rate = 1000000 kbps TailDrop Threshold = 1253376 bytes / 10 ms (default) WRED not configured for this class Level2 Class = class-default Egressq Queue ID = 1136 (Default LP queue) Queue Max. BW. = 50625 kbps (1 %) Queue Min. BW. = 0 kbps (default) Inverse Weight / Weight = 1 / (BWR not configured) Guaranteed service rate = 50000 kbps TailDrop Threshold = 62720 bytes / 10 ms (default) WRED not configured for this class

The statistics for the packets that have matched the different traffic classes of the parent and child traffic policies can be viewed using the command show policy-map interface interface-name output . Also, this command also shows the number of packets that are transmitted or dropped when the specified action is applied on the packets that have matched the respective traffic class.

Router# show policy-map interface ten0/0/0/10 outputTenGigE0/0/0/10 output: parentClass class-default Classification statistics (packets/bytes) (rate - kbps)  Matched : 2313578823/296138089344 8494665 Transmitted : 232805738/29799134464 854465 Total Dropped : 2080773085/266338954880 7640200 Policy child Class tc2 Classification statistics (packets/bytes) (rate - kbps)  Matched : 2313578823/296138089344 8494665 Transmitted : 232805738/29799134464 854465 Total Dropped : 2080773085/266338954880 7640200 Queueing statistics Queue ID : 1138 Taildropped(packets/bytes) : 2080773085/266338954880 Policy child Class class-default Classification statistics (packets/bytes) (rate - kbps)  Matched : 0/0 0 Transmitted : 0/0 0 Total Dropped : 0/0 0 Queueing statistics Queue ID : 1136 Taildropped(packets/bytes) : 0/0

When using hierarchical policers, there is no independent set of hardware counters to store the parent policer statistics. Instead, parent policer statistics are manipulated in the software to be the sum of all child policers under the same policy-map.

Configuration Example for Three-Level H-QoS

To configure three-level H-QoS:

Configure the port shaper or EFP group shaper.
Configure the two-level H-QoS policy with an EFP parent shaper and class or service level actions
Enable the port or EFP group shaper on the main interface to become the root policy.
Enable the two-level H-QoS policy on each EFP instance, thus providing a three-level hierarchy of service, EFP and EFP group or port SLAs.

A sample configuration for three-level H-QoS is as follows.

policy-map port_shaper class class-default shape average 6 gbps ! end-policy-map! policy-map efp_policy class class-default service-policy efp_policy_child shape average 4 gbps ! end-policy-map! policy-map efp_policy_child class tc1 shape average 50 mbps priority level 1 ! class tc2 bandwidth percent 50 ! class tc3 bandwidth percent 30 ! class class-default ! end-policy-map! interface TenGigE0/5/0/4 service-policy output port_shaper!interface TenGigE0/5/0/4.1 service-policy output efp_policy encapsulation dot1q 11!interface TenGigE0/5/0/4.2 service-policy output efp_policy encapsulation dot1q 12!

Verification

Run the show policy-map interface command in XR EXEC mode to display the packet/byte count and rate post port shaper enforcement on each of the sub-interface/EFP policies.

Bandwidth Remaining Ratio at Parent Level

Table 2. Feature History Table
Feature Name	Release Information	Feature Description
Bandwidth Remaining Ratio at Parent Level	Release 7.10.1	You can now provide preference to a specific user assigned to a subinterface. With this feature, the bandwidth remaining ratio (BWRR) is applied at the parent traffic policy level to control the low-priority traffic at the subinterface level. During congestion, the subinterface with the higher BWRR gets more bandwidth allocation that allows traffic to flow. Earlier, the BWRR in H-QoS was supported only at the child policy level. Supported on the following Cisco NCS 540 variants: N540-ACC-SYS N540X-ACC-SYS N540-24Z8Q2C-SYS

Hierarchical QoS (H-QoS) allows you to specify QoS behavior at multiple policy levels, and starting from Cisco IOS XR Release 7.10.1 you can allocate weights corresponding to the bandwidth remaining ratio (BWRR) at the parent traffic policy level. The bandwidth remaining option specifies a weight at parent policy level for the subinterface. After the priority-queue is serviced, the leftover bandwidth is distributed as per BWRR. For more information on BWRR, see Bandwidth Remaining.

You can configure the BWRR on parent traffic policy on the subinterfaces belonging to the same physical interface. You can configure the parent policy of the subinterfaces, with different weights. Subinterfaces with more weight get more bandwidth.

For example, consider the use case where three subinterfaces belonging to same physical interface (1G) configured with H-QoS policy. All three subinterface policies are configured with 500 Mbps parent shaper each. When all three try to use the assigned bandwidth, it requires 1.5G in total bandwidth exceeding 1G and it results in congestion. If on these three subinterfaces the BWRR weights are configured as 20, 40, and 60 each, then the subinterface with higher BWRR allows more traffic to flow.

Restrictions and Limitations

Weight sharing is applied only on low-priority traffic. For more information on sharing of weights, see Shared Policer.

Configuring BWRR at H-QoS

Before you configure H-QoS, you must enable the H-QoS profile on the router. After enabling H-QoS profile, reload the router, for more information see Configuring Hierarchical Queuing.

In the following example you’ll create three traffic policies with BWRR as 20, 40, and 60, respectively. These policies will be applied to a 10G subinterface, with BWRR applied to each parent 1, 2, and 3. The subinterface parent 3, has more weightage of 60 than the other two parent subinterfaces.

Configuration of a parent traffic policy 1 is as follows:

Router# configureRouter(config)# policy-map hqos_bw_remaining_ratio_parent_1Router(config-pmap)# class class-defaultRouter(config-pmap-c)# service-policy hqos_child_1Router(config-pmap-c)# bandwidth remaining ratio 20 Router(config-pmap)# exitRouter(config)# commit

Configuration of a parent traffic policy 2 is as follows:

Router# configureRouter(config)# policy-map hqos_bw_remaining_ratio_parent_2Router(config-pmap)# class class-defaultRouter(config-pmap-c)# service-policy hqos_child_2Router(config-pmap-c)# bandwidth remaining ratio 40 Router(config-pmap)# exitRouter(config)# commit

Configuration of a parent traffic policy 3 is as follows:

Router# configureRouter(config)# policy-map hqos_bw_remaining_ratio_parent_3Router(config-pmap)# class class-defaultRouter(config-pmap-c)# service-policy hqos_child_3Router(config-pmap-c)# bandwidth remaining ratio 60 Router(config-pmap)# exitRouter(config)# commit

In the following example, the policy maps are assigned to the subinterfaces.

Router# configureRouter(config)# interface TenGigE0/0/0/20Router(config-if)# service-policy output shaper_verification_parentRouter(config-if)# interface TenGigE0/0/0/20.103Router(config-subif)# service-policy output hqos_bw_remaining_ratio_parent_1 Router(config-subif)# interface TenGigE0/0/0/20.1Router(config-subif)# service-policy output hqos_bw_remaining_ratio_parent_2Router(config-subif)# interface TenGigE0/0/0/20.101Router(config-subif)# service-policy output hqos_bw_remaining_ratio_parent_3

Running Configuration

/* Configuration of a Parent Traffic Policy 1*/hqos_bw_remaining_ratio_parent_1 class class-default service-policy hqos_child_1 bandwidth remaining ratio 20 ! end-policy-map! /* Configuration of a Parent Traffic Policy 2*/hqos_bw_remaining_ratio_parent_2 class class-default service-policy hqos_child_2 bandwidth remaining ratio 40 ! end-policy-map! /* Configuration of a Parent Traffic Policy 3*/hqos_bw_remaining_ratio_parent_3 class class-default service-policy hqos_child_3 bandwidth remaining ratio 60 ! end-policy-map!

Verification

Verify the H-QoS traffic policy that is applied on the interface using the commands show qos interface interface-name output.

The following example shows the output of all three parent traffic policies, but the subinterface policy-map hqos_bw_remaining_ratio_parent_3 gets more bandwidth allocation that allows traffic to flow.

RP/0/RP0/CPU0:ios#show qos interface TenGigE0/0/0/20.103 outputNOTE:- Configured values are displayed within parenthesesInterface TenGigE0/0/0/20.103 ifh 0x8152 -- output policyNPU Id: 0Total number of classes: 9Interface Bandwidth: 10000000 kbpsPolicy Name: hqos_bw_remaining_ratio_parent_1SPI Id: 0x0VOQ Base: 1320PFC enabled: 0Accounting Type: Layer1 (Include Layer 1 encapsulation and above)------------------------------------------------------------------------------Level1 Class = class-defaultQueue Max. BW. = no max (default)Queue Min. BW. = 0 kbps (default)Inverse Weight / Weight = 1 / (20)RP/0/RP0/CPU0:ios#show qos interface TenGigE0/0/0/20.1 outputNOTE:- Configured values are displayed within parenthesesInterface TenGigE0/0/0/20.1 ifh 0x8152 -- output policyNPU Id: 0Total number of classes: 9Interface Bandwidth: 10000000 kbpsPolicy Name: hqos_bw_remaining_ratio_parent_2SPI Id: 0x0VOQ Base: 1320PFC enabled: 0Accounting Type: Layer1 (Include Layer 1 encapsulation and above)------------------------------------------------------------------------------Level1 Class = class-defaultQueue Max. BW. = no max (default)Queue Min. BW. = 0 kbps (default)Inverse Weight / Weight = 1 / (40)RP/0/RP0/CPU0:ios#show qos interface ten0/0/0/20.101 outputNOTE:- Configured values are displayed within parenthesesInterface TenGigE0/0/0/20.101 ifh 0x81a0 -- output policyNPU Id: 0Total number of classes: 9Interface Bandwidth: 10000000 kbpsPolicy Name: hqos_bw_remaining_ratio_parent_3 /* BWRR with more weightage */SPI Id: 0x0VOQ Base: 1296PFC enabled: 0Accounting Type: Layer1 (Include Layer 1 encapsulation and above)------------------------------------------------------------------------------Level1 Class = class-defaultQueue Max. BW. = no max (default)Queue Min. BW. = 0 kbps (default)Inverse Weight / Weight = 1 / (60) /* BWRR with more weightage */

Conform Aware Hierarchical Policy Overview

Hierarchical QoS (H-QoS), while allowing for granular and multi-level management of traffic, does not allow for conform traffic from a child-level policy to a parent-level policy to get priority. This means that in case of excess traffic, the parent policer drops conform traffic packets from the child level as well.

Modular QoS Configuration Guide for Cisco NCS 540 Series Routers, Cisco IOS XR Release 7.10.x - Configuring Hierarchical Modular QoS [Cisco Network Convergence System 540 Series Routers] (1)

The conform-aware hierarchical policy feature enables the parent-level policy to prioritize conform traffic from child-level policy over exceed and violate traffic.

Here is how it works: the child-level policer initially marks its packets as red, yellow, or green. Packets are marked based on the committed information rate (CIR) value and the two associated burst sizes - committed burst size (CBS) and excess burst size (EBS). If a packet does not exceed the CBS, it is marked as conformed packet (green). The packet is marked as exceeded if it exceeds CBS, but not the EBS (yellow). If it exceeds the EBS as well, it is marked as violate packet (red).

When the packets arrive at the parent level policer (which is color aware), the policer prioritizes the packets marked green over the packets marked yellow. After all the conform traffic (green) is transmitted and there are tokens available still, the yellow packets are transmitted next, instead of being marked as violate traffic (red).

To enable the conform-aware hierarchical policy feature run the command.

hw-module profile qos conform-aware-policer

Configuring Conform Aware Hierarchy Policy

To enable and configure shared policer:

Run the hw-module profile qos conform-aware-policer command.
Reload the affected line card.
Configure class maps to be used for matching packets to the class specified.
Create a child policy map.
Configure traffic policing for the classes in the child policy map.
Attach the child policy-map to the parent’s class-default class.
Configure traffic policing for the parent policy map.

RP/0/RP0/CPU0:ios(config)#hw-module profile qos conform-aware-policer/* To activate this profile, you must manually reload the chassis or all line cards */RP/0/RP0/CPU0:ios(config)#exitUncommitted changes found, commit them before exiting(yes/no/cancel)? [cancel]:yesRP/0/RP0/CPU0:router# reload location 0/0/CPU0RP/0/RSP0/CPU0:ios(config)# policy-map CHILD-INGRESSRP/0/RSP0/CPU0:ios(config-pmap)# class REAL-TIMERP/0/RSP0/CPU0:ios(config-pmap-c)# set traffic-class 5RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 20 mbpsRP/0/RSP0/CPU0:ios(config-pmap)# class NET-CONTROLRP/0/RSP0/CPU0:ios(config-pmap-c)# set traffic-class 4RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 5 mbpsRP/0/RSP0/CPU0:ios(config-pmap)# class DATA1RP/0/RSP0/CPU0:ios(config-pmap-c)# set traffic-class 3RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 5 mbpsRP/0/RSP0/CPU0:ios(config-cmap)# set qos-group 3RP/0/RSP0/CPU0:ios(config-cmap)# class DATA2RP/0/RSP0/CPU0:ios(config-pmap-c)# set traffic-class 2RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 5 mbpsRP/0/RSP0/CPU0:ios(config-cmap)# set qos-group 3RP/0/RSP0/CPU0:ios(config-pmap-c)#class class-defaultRP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 10 mbpsRP/0/RSP0/CPU0:ios(config-pmap)#end-policy-mapRP/0/RSP0/CPU0:ios(config)# policy-map PARENT-INGRESSRP/0/RSP0/CPU0:ios(config-pmap)#class class-defaultRP/0/RSP0/CPU0:ios(config-cmap-c)# service-policy CHILD-INGRESSRP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 100 mbpsRP/0/RSP0/CPU0:ios(config-pmap)#end-policy-mapRP/0/RSP0/CPU0:ios(config-pmap)#RP/0/RSP0/CPU0:ios(config-pmap)# interface GigabitEthernet0/0/0/22.13RP/0/RSP0/CPU0:ios(config-pmap)# service-policy in parent-policerRP/0/RSP0/CPU0:ios (config-subif)#endUncommitted changes found, commit them before exiting(yes/no/cancel)? [cancel]:yes

Running Configuration

RP/0/RP0/CPU0:ios#show run interface GigabitEthernet0/0/0/22.13Tue Feb 23 20:45:08.889 GMTinterface GigabitEthernet0/0/0/22.13 description Testing interface service-policy input parent-policer vrf customer1 ipv4 address 172.16.1.1 255.255.255.252policy-map PARENT-INGRESS class class-default service-policy CHILD-INGRESS police rate 100 mbps !end-policy-map!policy-map CHILD-INGRESS class REAL-TIME set traffic-class 5 police rate 20 mbps ! class NET-CONTROL set traffic-class 4 police rate 5 mbps ! class DATA1 set traffic-class 3 police rate 5 mbps set qos-group 3 ! class DATA2 set traffic-class 2 police rate 5 mbps set qos-group 3 ! class class-default police rate 10 mbps!end-policy-map

RP/0/RSP0/CPU0:ios(config)#policy-map parent-policerRP/0/RSP0/CPU0:ios(config-pmap)#class class-defaultRP/0/RSP0/CPU0:ios(config-pmap-c)#service-policy child-policerRP/0/RSP0/CPU0:ios(config-pmap-c)#police rate 30 mbps peak-rate 30 mbpsRP/0/RSP0/CPU0:ios(config-pmap-c-police)#end-policy-mapRP/0/RSP0/CPU0:ios(config)# policy-map child-policerRP/0/RSP0/CPU0:ios(config-pmap)# class cos3RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 10 mbps peak-rate 30 mbpsRP/0/RSP0/CPU0:ios(config-pmap)# class cos4RP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 15 mbps peak-rate 30 mbpsRP/0/RSP0/CPU0:ios(config-pmap-c)#class class-defaultRP/0/RSP0/CPU0:ios(config-pmap-c-police)#police rate 5 mbps peak-rate 30 mbpsRP/0/RSP0/CPU0:ios(config-pmap)#end-policy-map

Running Configuration

RP/0/RP0/CPU0:ios#show run policy-map parent-policerTue Feb 23 19:37:57.500 GMTpolicy-map parent-policer class class-default service-policy child-policer police rate 30 mbps peak-rate 30 mbps ! end-policy-mapRP/0/RP0/CPU0:ios#show run policy-map child-policerTue Feb 23 19:38:35.472 GMTpolicy-map child-policer class cos3 police rate 10 mbps peak-rate 30 mbps ! class cos4 police rate 15 mbps peak-rate 30 mbps ! class class-default police rate 5 mbps peak-rate 30 mbps ! end-policy-map

Verification

Run the show policy-map interface command in XR EXEC mode to confirm that the committed information rate (CIR) is prioritized over the peak information rate (PIR).

In the example below, Policed (conform) or CIR from each class is prioritized over Policed (exceed) or PIR.

RP/0/RP0/CPU0:ios# show policy-map interface GigabitEthernet0/0/0/22.13 input GigabitEthernet0/0/0/22.13 input: parent-policer Class class-default Classification statistics (packets/bytes) (rate - kbps) Matched : 217797200/111512166400 2344847 Transmitted : 8314388/4256966656 88089 Total Dropped : 209482812/107255199744 2256758 Policing statistics (packets/bytes) (rate - kbps) Policed(conform) : 6602174/3380313088 69926 Policed(exceed) : 1712214/876653568 18165 Policed(violate) : 209482812/107255199744 2256782 Policed and dropped : 209482812/107255199744 Policy child-policer Class cos3 Classification statistics (packets/bytes) (rate - kbps) Matched : 54449300/27878041600 586215 Transmitted : 3246813/1662368256 34399 Total Dropped : 51202487/26215673344 551816 Policing statistics (packets/bytes) (rate - kbps) Policed(conform) : 2818471/1443057152 29851 Policed(exceed) : 428342/219311104 4547 Policed(violate) : 51202487/26215673344 551816 Policed and dropped : 51202487/26215673344 Policed and dropped(parent policer) : 0/0 Policy child-policer Class cos4 Classification statistics (packets/bytes) (rate - kbps) Matched : 54449300/27878041600 586213 Transmitted : 2319731/1187702272 24577 Total Dropped : 52129569/26690339328 561636 Policing statistics (packets/bytes) (rate - kbps) Policed(conform) : 1891851/968627712 20037 Policed(exceed) : 427880/219074560 4540 Policed(violate) : 52129569/26690339328 561636 Policed and dropped : 52129569/26690339328 Policed and dropped(parent policer) : 0/0 Policy child-policer Class class-default Classification statistics (packets/bytes) (rate - kbps) Matched : 108898600/55756083200 1172419 Transmitted : 2747844/1406896128 29113 Total Dropped : 106150756/54349187072 1143306 Policing statistics (packets/bytes) (rate - kbps) Policed(conform) : 1891852/968628224 20036 Policed(exceed) : 855992/438267904 9076 Policed(violate) : 106150756/54349187072 1143306 Policed and dropped : 106150756/54349187072 Policed and dropped(parent policer) : 0/0

Related Commands

hw-module profile qos conform-aware-policer

Conform Aware Hierarchical Policy Restrictions

The parent-policy traffic police rate must be greater than or equal to the sum of child conform rates.

The Confirm-Aware hierarchical policer function allows the child level policy to color the traffic as either green, yellow, or red for handling at the parent-level policer.
All classes in the child-level of the QoS policy need to have a policer configured for their packets to be handled correctly by the parent policer.