Setup Guide
Figure 28. CoPP Implemented Versus CoPP Not Implemented
Congure Control Plane Policing
The system can process a maximum of 4200 packets per second (PPS). Protocols that share a single queue may experience aps if one of
the protocols receives a high rate of control trac even though per protocol CoPP is applied. This happens because queue-based rate
limiting is applied rst.
For example, border gateway protocol (BGP) and internet control message protocol (ICMP) share same queue (Q6); Q6 has 400 PPS of
bandwidth by default. The desired rate of ICMP is 100 PPS and the remaining 300 PPS is assigned to BGP. If ICMP packets come at 400
PPS, BGP packets may be dropped though ICMP packets are rate-limited to 100 PPS. You can solve this by increasing Q6 bandwidth to
700 PPS to allow both ICMP and BGP packets and then applying per-ow CoPP for ICMP and BGP packets. The setting of this Q6
bandwidth is dependent on the incoming trac for the set of protocols sharing the same queue. If you are not aware of the incoming
protocol trac rate, you cannot set the required queue rate limit value. You must complete queue bandwidth tuning carefully because the
system cannot open up to handle any rate, including trac coming at the line rate.
CoPP policies are assigned on a per-protocol or a per-queue basis, and are assigned in CONTROL-PLANE mode to each port-pipe.
CoPP policies are congured by creating extended ACL rules and specifying rate-limits through QoS policies. The ACLs and QoS policies
are assigned as service-policies.
Control Plane Policing (CoPP)
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