Administrator Guide

3. Enter Control Plane mode.
CONFIGURATION mode
control-plane-cpuqos
4. Assign a CPU queue-based service policy on the control plane in cpu-qos mode. Enabling this command sets the queue rates
according to those configured.
CONTROL-PLANE mode
service-policy rate-limit-cpu-queues name
The following example shows creating the QoS policy.
Dell#conf
Dell(conf)#qos-policy-input cpuq_1
Dell(conf-qos-policy-in)#rate-police 3000 40 peak 500 40
Dell(conf-qos-policy-in)#exit
Dell(conf)#qos-policy-input cpuq_2
Dell(conf-qos-policy-in)#rate-police 5000 80 peak 600 50
Dell(conf-qos-policy-in)#exit
The following example shows assigning the QoS policy to the queues.
Dell(conf)#policy-map-input cpuq_rate_policy cpu-qos
Dell(conf-qos-policy-in)#service-queue 5 qos-policy cpuq_1
Dell(conf-qos-policy-in)#service-queue 6 qos-policy cpuq_2
Dell(conf-qos-policy-in)#service-queue 7 qos-policy cpuq_1
The following example shows creating the control plane service policy.
Dell#conf
Dell(conf)#control-plane
Dell(conf-control-plane)#service-policy rate-limit-cpu-queues cpuq_rate_policy
CoPP for OSPFv3 Packets
You can create an IPv6 ACL for control-plane traffic policing for OSPFv3, in addition to the CoPP support for VRRP, BGP,
and ICMP. You can use the ipv6 access-list name cpu-qos permit ospfv3 command to allow CoPP traffic for
OSPFv3. Control Plane Policing (CoPP) enables more number of CPU queues 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 on CMIC port and sending
control packets to different queues that internally reduce limitation or contention of control protocols sharing the same queues
(that is, before this functionality of CoPP for OSPV3 was introduced, OSPF might have caused the LACP flap because of both
control traffic sent to same Q7 on CPU port). Non CPU port should have only 4 dedicated control queues and remaining shared
for both data and traffic. Number of control queues is increased on the CPU port. When tunneling packets from non-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 the ICMPv6 packets and
unknown IPv6 packets. Due to this NS/NA/RS/RA packets not given high priority leads to the session establishment problem.
To solve this issue, starting from release 9.4.(0.0), IPv6 NDP packets use different CPU queues when compared to the Generic
IPv6 multicast traffic. These entries are installed in system when application is triggered..
CPU Processing of CoPP Traffic
The systems use FP rules to take the packets to control plane by CopyToCPU or redirect packet to CPU port. Only 8 CPU
queues are used while sending the packet to CPU. The CPU Management Interface Controller (CMIC) interface on all the
systems supports 48 queues in hardware. However, FTOS supports only 8 CMIC queues – 4 for data streams that are CPU
bound – SFLOW packets, packet streams that are trapped to CPU for logging info on MAC learn limit exceeded and other
violations, L3 packets with unknown destination for soft forwarding etc. Other 4 CMIC queues will carry the L2/L3 well-known
protocol streams. However there are about 20 well known protocol streams that have to share these 4 CMIC queues. Before
9.4.(0.0)Dell Networking OS used only 8 queues most of the queues are shared to multiple protocols. So, increasing the number
of CMIC queues will reduce the contention among the protocols for the queue bandwidth.
Control Plane Policing (CoPP)
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