The following example shows assigning the QoS policy to the queues.Dell(conf)#policy-map-input cpuq_rate_policy cpu-qosDell(conf-qos-policy-in)#service-queue 5 qos-policy cpuq_1Dell(conf-qos-policy-in)#service-queue 6 qos-policy cpuq_2Dell(conf-qos-policy-in)#service-queue 7 qos-policy cpuq_1The following example shows creating the control plane service policy.Dell#confDell(conf)#control-planeDell(conf-control-plane)#service-policy rate-limit-cpu-queues cpuq_rate_policyCoPP for OSPFv3 PacketsYou can create an IPv6 ACL for control-plane traffic policing for OSPFv3, in addition to the CoPP supportfor VRRP, BGP, and ICMP. You can use the ipv6 access-list name cpu-qos permit ospfv3command to allow CoPP traffic for OSPFv3. Control Plane Policing (CoPP) enables more number of CPUqueues to be made available on ports for IPv6 and ICMPv6 packets.CoPP enhancements are to enhance the capability of FTOS by utilizing more number of CPU queues onCMIC port and sending control packets to different queues that internally reduce limitation or contentionof control protocols sharing the same queues (that is, before this functionality of CoPP for OSPV3 wasintroduced, OSPF might have caused the LACP flap because of both control traffic sent to same Q7 onCPU port). Non CPU port should have only 4 dedicated control queues and remaining shared for bothdata and traffic. Number of control queues is increased on the CPU port. When tunneling packets fromnon-master to master unit, high-gig queues are used.Prior to the release 9.4.(0.0), all IPv6 packets are taken to same queues there is no priority between theICMPv6 packets and unknown IPv6 packets. Due to this NS/NA/RS/RA packets not given high priorityleads to the session establishment problem. To solve this issue, starting from release 9.4.(0.0), IPv6 NDPpackets use different CPU queues when compared to the Generic IPv6 multicast traffic. These entries areinstalled in system when application is triggered..CPU Processing of CoPP TrafficThe systems use FP rules to take the packets to control plane by CopyToCPU or redirect packet to CPUport. Only 8 CPU queues are used while sending the packet to CPU. The CPU Management InterfaceController (CMIC) interface on all the systems supports 48 queues in hardware. However, FTOS supportsonly 8 CMIC queues – 4 for data streams that are CPU bound – SFLOW packets, packet streams that aretrapped to CPU for logging info on MAC learn limit exceeded and other violations, L3 packets withunknown destination for soft forwarding etc. Other 4 CMIC queues will carry the L2/L3 well-knownprotocol streams. However there are about 20 well known protocol streams that have to share these 4CMIC queues. Before 9.4.(0.0)Dell Networking OS used only 8 queues most of the queues are shared tomultiple protocols. So, increasing the number of CMIC queues will reduce the contention among theprotocols for the queue bandwidth.Currently, there are 4 Queues for data and 4 for control in both front-end and back-plane ports. Instacked systems, the control streams that reach standby or slave units will be tunneled through thebackplane ports across stack-units to reach the CPU of the master unit. In this case, the packets thatreach slave unit’s CMIC via queues 0 – 7 will take same queues 0 – 7 on the back-plane ports whiletraversing across units and finally on the master CMIC, they are queued on the same queues 0 – 7. In thiscase, the queue (4 – 7) taken by the well-known protocol streams are uniform across different queuing242 Control Plane Policing (CoPP)
