Configuring Policing; About Policing; Shared Policers - Cisco Nexus 9000 Series Configuration Manual

Configuring Policing

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About Policing

Policing is the monitoring of the data rates for a particular class of traffic. When the data rate exceeds
user-configured values, marking or dropping of packets occurs immediately. Policing does not buffer the
traffic; therefore, the transmission delay is not affected. When traffic exceeds the data rate, you instruct the
system to either drop the packets or mark QoS fields in them.
You can define single-rate and dual-rate policers.
Single-rate policers monitor the committed information rate (CIR) of traffic. Dual-rate policers monitor both
CIR and peak information rate (PIR) of traffic. In addition, the system monitors associated burst sizes. Three
colors, or conditions, are determined by the policer for each packet depending on the data rate parameters
supplied: conform (green), exceed (yellow), or violate (red).
You can configure only one action for each condition. For example, you might police for traffic in a class to
conform to the data rate of 256000 bits per second, with up to 200 millisecond bursts. The system would apply
the conform action to traffic that falls within this rate, and it would apply the violate action to traffic that
exceeds this rate.
For more information about policers, see RFC 2697 and RFC 2698.

Shared Policers

Note The shared policer feature is only supported on the Cisco Nexus 9508 switch (NX-OS 7.0(3)F3(3) and later
7.0(3)F3(x) releases).
About Policing, on page 85
Shared Policers, on page 85
Prerequisites for Policing, on page 86
Guidelines and Limitations, on page 86
Configuring Policing, on page 88
Configuring Shared Policers, on page 97
Verifying the Policing Configuration, on page 99
Configuration Examples for Policing, on page 99
Cisco Nexus 9000 Series NX-OS Quality of Service Configuration Guide, Release 7.x
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