protects the Route Processor (RP) from having to process noncritical traffic,
which increases the CPU bandwidth available to critical traffic. Traffic is
placed into different CPU queues based on various criteria. The Punt Policing
and Monitoring feature allows you to police the punt rate on a per-queue basis.
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.
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Packets received on an interface are punted to the Router Processor (RP) for various reasons. Some examples of these various reasons include, unicast and multicast control plane traffic that are destined for a routing protocol process running on the RP, and IP packets that generate Internet Control Message Protocol (ICMP) exceptions such as a Time to live (TTL) expiration. The RP has a limited capacity to process the punted packets, and while some of them are critical for the router operation and should not be dropped, some can be dropped without impacting the router operation.
Punt policing frees the RP from having to process noncritical traffic. Traffic is placed in queues based on various criteria, and you can configure the maximum punt rate for each queue which allows you to configure the system so that packets are less likely to be dropped from queues that contain critical traffic.
Traffic on certain CPU queues could still be dropped, regardless of the configured punt rate, based on other criteria such as the queue priority, queue size, and traffic punt rate.
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Feature Information for Punt Policing and Monitoring
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
An account on Cisco.com is not required.
Table 1 Feature Information for Punt Policing and Monitoring
Punt Policing and Monitoring
Cisco IOS XE Release 3.5S
The Punt Policing and Monitoring feature allows you to specify a maximum punt rate on a per-queue basis.
For Cisco IOS XE Release 3.5S, this feature was implemented on Cisco ASR 903 Router.
The following command was introduced:
platform punt-police queue