Cisco Systems OL-4266-08 manual 42-77

Chapter 42 Configuring PFC QoS

Configuring PFC QoS

When configuring a per-interface policer, note the following information:

•Aggregate policing works independently on each DFC-equipped switching module and independently on the PFC, which supports any non-DFC-equipped switching modules. Aggregate policing does not combine flow statistics from different DFC-equipped switching modules. You can display aggregate policing statistics for each DFC-equipped switching module and for the PFC and any non-DFC-equipped switching modules supported by the PFC.

•Each PFC or DFC polices independently, which might affect QoS features being applied to traffic that is distributed across the PFC and any DFCs. Examples of these QoS feature are:

–Policers applied to a port channel interface.

–Policers applied to a switched virtual interface.

–Egress policers applied to either a Layer 3 interface or an SVI. Note that PFC QoS performs egress policing decisions at the ingress interface, on the PFC or ingress DFC.

Policers affected by this restriction deliver an aggregate rate that is the sum of all the independent policing rates.

•With a PFC3, when you apply both ingress policing and egress policing to the same traffic, both the input policy and the output policy must either mark down traffic or drop traffic. PFC QoS does not support ingress markdown with egress drop or ingress drop with egress markdown.

•With Release 12.2(18)SXE and later releases, you can apply aggregate and microflow policers to IPv6 traffic.

•With a PFC3, policing uses the Layer 2 frame size.

•With a PFC2, policing uses the Layer 3 packet size.

•See the “PFC QoS Configuration Guidelines and Restrictions” section on page 42-49for information about rate and burst size granularity.

•You can enter the flow keyword to define a microflow policer (you cannot apply microflow policing to ARP traffic). When configuring a microflow policer, note the following information:

–With a PFC3, you can enter the mask src-onlykeywords to base flow identification only on source addresses, which applies the microflow policer to all traffic from each source address. Release 12.2(17d)SXB and later releases support the mask src-onlykeywords for both IP traffic and MAC traffic. Releases earlier than Release 12.2(17d)SXB support the mask src-onlykeywords only for IP traffic.

–With a PFC3, you can enter the mask dest-onlykeywords to base flow identification only on destination addresses, which applies the microflow policer to all traffic to each source address. Release 12.2(17d)SXB and later releases support the mask dest-onlykeywords for both IP traffic and MAC traffic. Releases earlier than Release 12.2(17d)SXB support the mask dest-onlykeywords only for IP traffic.

–By default and with the mask full-flowkeywords, PFC QoS bases IP flow identification on source IP address, destination IP address, the Layer 3 protocol, and Layer 4 port numbers.

–With a PFC2, PFC QoS considers IPX traffic with same source network, destination network, and destination node to be part of the same flow, including traffic with different source nodes or sockets.

–PFC QoS considers MAC-Layer traffic with the same protocol and the same source and destination MAC-Layer addresses to be part of the same flow, including traffic with different EtherTypes.

–Microflow policers do not support the maximum_burst_bytes parameter, the pir bits_per_second keyword and parameter, or the violate-actionkeyword.

	Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08		42-77