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User-configured ACLs that filter protocol traffic flows to the control plane are automatically applied or disabled as the
corresponding protocol is enabled or disabled in the system. In this way, control packets from disabled protocols never reach the
control plane.
Protocol-based Control Plane Policing
To configure a protocol-based CoPP policy, you create an extended ACL rule for the protocol and specify the rate limit in a QoS
policy. It is not necessary to specify the CPU queue because the protocol-queue mapping is handled internally by the system. To
display the protocol-queue mapping for protocols that you can configure for protocol-based CoPP, enter the show {mac | ip |
ipv6} protocol-queue-mapping command.
Queue-based Control Plane Policing
When configuring a queue-based CoPP policy, take into account that there are twenty-four CP queues divided into groups of
eight queues for the Route Processor, Control Processor, and line-card CPUs:
● Queues 0 to 7 process packets destined to the Control Processor CPU .
● Queues 8 to 15 process packets destined to the Route Processor CPU.
● Queues 16 to 23 process packets destined to the line-card CPU.
The protocols mapped to each CPU queue and the default rate limit applied to the eight CPU queues for the Route Processor,
Control Processor, and line cards are as follows:
Table 11. Default Rate Limit for CPU queues
CPU Queue Protocols Mapped to Control Processor Queues Rate Limit (in kbps)
0 TTL0, IP options, L3 Broadcast MAC destination address 1000
1 L3 MTU Fail 200
2 ARP request, NS, RS 1800
3 ARP reply, NA, RA 1800
4 FTP, Telnet, SSH, Local terminated, NTP, VLT IPM PDU, VLT ARPM 2800
5 ICMPv6 300
6 ICMP 300
7 DHCP, LLDP, FEFD, 8021x 3200
Table 12. Default Rate Limit for Route Processor queues
CPU Queue Protocols Mapped to Route Processor Queues Rate Limit (in kbps)
8 Unknown L3, L3 with Broadcast MAC destination address 400
9 PIM DR, Multicast Catch All, iSCSI, IPv6 Multicast Catch All, IPv6
Multicast tunnels
400
10 ARP request, NS, RS 1800
11 ARP reply, NA, RA 1800
12 VLT 2000
13 BFD 5200
14 PVST, GVRP, FCoE, OpenFlow, IGMP, PIM, MLD, MSDP 1850
15 STP, L2PT, LACP, ECFM, BGP, RIP, OSPF, IS-IS, VRRP 12450
Table 13. Default Rate Limit for Line-Card queues
CPU Queue Protocols Mapped to Line-Card CPU Queues Rate Limit (in kbps)
210 Control Plane Policing (CoPP)