Cisco Systems OL-4266-08 manual PFC2 Guidelines, 42-52

Chapter 42 Configuring PFC QoS

PFC QoS Configuration Guidelines and Restrictions

•The QoS features implemented in the port ASICs (queue architecture and dequeuing algorithms) support IPv4 and IPv6 traffic.

•The PFC3 supports IPv6 named extended ACLs and named standard ACLs.

•In Release 12.2(18)SXE and later releases, the PFC3 supports the match protocol ipv6 command.

•Because of conflicting TCAM lookup flow key bit requirements, you cannot configure IPv6 DSCP-based filtering and IPv6 Layer 4 range-based filtering on the same interface. For example:

–If you configure both a DSCP value and a Layer 4 “greater than” (gt) or “less than” (lt) operator in an IPv6 ACE, you cannot use the ACL for PFC QoS filtering.

–If you configure a DSCP value in one IPv6 ACL and a Layer 4 “greater than” (gt) or “less than” (lt) operator in another IPv6 ACL, you cannot use both ACLs in different class maps on the same interface for PFC QoS filtering.

•In Release 12.2(18)SXE and later releases, you can apply aggregate and microflow policers to IPv6 traffic, but you cannot apply microflow policing to IPv6 multicast traffic.

•With egress ACL support for remarked DSCP configured, the PFC3 does not provide hardware-assistance for these features:

–Cisco IOS reflexive ACLs

–TCP intercept

–Context-Based Access Control (CBAC)

–Network Address Translation (NAT)

•With a PFC3, you cannot apply microflow policing to ARP traffic.

•The PFC3 does not apply egress policing to traffic that is being bridged to the MSFC3.

•The PFC3 does not apply egress policing or egress DSCP mutation to multicast traffic from the MSFC3.

•With a PFC3, PFC QoS does not rewrite the ToS byte in bridged multicast traffic.

PFC2 Guidelines

•The PFC2 supports the match protocol class map command, which configures NBAR and sends all traffic on the Layer 3 interface, both ingress and egress, to be processed in software on the MSFC2. To configure NBAR, refer to this publication:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t8/dtnbarad.htm

•The PFC2 does not support these PFC QoS features:

–Egress policing

–Egress DSCP mutation

–DSCP Transparency

–VLAN-based QoS with DFCs installed

•The PFC2 does not support the modules that support ingress CoS mutation on IEEE 802.1Q tunnel ports.

	Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
42-52	OL-4266-08