Cisco Systems OL-4266-08 Network Router User Manual


 
CHAPTER
42-1
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
42
Configuring PFC QoS
This chapter describes how to configure quality of service (QoS) as implemented on the Policy Feature
Card (PFC) and Distributed Forwarding Cards (DFCs) on the Cisco 7600 series routers.
Note For complete syntax and usage information for the commands used in this chapter, refer to the
Cisco 7600 Series Router Cisco IOS Command Reference at this URL:
http://www.cisco.com/univercd/cc/td/doc/product/core/cis7600/software/122sx/cmdref/index.htm
For information about QoS and MPLS, see Chapter 43, “Configuring PFC3BXL or PFC3B Mode
MPLS QoS.”
QoS on the Cisco 7600 series routers (PFC QoS) uses some Cisco IOS modular QoS CLI (MQC).
Because PFC QoS is implemented in hardware, it supports only a subset of the MQC syntax.
The PFC3 does not support Network-Based Application Recognition (NBAR).
With a Supervisor Engine 2, PFC2, and MSFC2, you can configure NBAR on Layer 3 interfaces
instead of PFC QoS:
The PFC2 provides hardware support for input ACLs on ports where you configure NBAR.
When PFC QoS is enabled, the traffic through ports where you configure NBAR passes through
the ingress and egress queues and drop thresholds.
When PFC QoS is enabled, the MSFC2 sets egress CoS equal to egress IP precedence in NBAR
traffic.
After passing through an ingress queue, all traffic is processed in software on the MSFC2 on
interfaces where you configure NBAR.
To configure NBAR, refer to this publication:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t8/dtnba
rad.htm
This chapter contains these sections:
Understanding How PFC QoS Works, page 42-2
PFC QoS Default Configuration, page 42-28
PFC QoS Configuration Guidelines and Restrictions, page 42-49
Configuring PFC QoS, page 42-55
Common QoS Scenarios, page 42-112
PFC QoS Glossary, page 42-122