Pfc Qos Configuration Guidelines And Restrictions; General Guidelines - Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual

Chapter 38 Configuring PFC QoS

PFC QoS Configuration Guidelines and Restrictions

When configuring PFC QoS, follow these guidelines and restrictions:
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General Guidelines

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OL-11439-03
General Guidelines, page 38-39
PFC3B Guidelines, page 38-41
Class Map Command Restrictions, page 38-42
Policy Map Command Restrictions, page 38-42
Policy Map Class Command Restrictions, page 38-42
Supported Granularity for CIR and PIR Rate Values, page 38-42
Supported Granularity for CIR and PIR Token Bucket Sizes, page 38-43
IP Precedence and DSCP Values, page 38-44
QoS features implemented on port ASICs are supported on interfaces where you configure
PISA-accelerated features.
QoS features implemented on the PFC are not supported on interfaces where you configure
PISA-accelerated features.
The match ip precedence and match ip dscp commands filter only IPv4 traffic.
The match precedence and match dscp commands filter IPv4 and IPv6 traffic.
The set ip dscp and set ip precedence commands are saved in the configuration file as set dscp and
set precedence commands.
PFC QoS supports the set dscp and set precedence policy map class commands for IPv4 and IPv6
traffic.
The flowmask requirements of QoS, NetFlow, and NetFlow data export (NDE) might conflict,
especially if you configure microflow policing.
With egress ACL support for remarked DSCP and VACL capture both configured on an interface,
VACL capture might capture two copies of each packet, and the second copy might be corrupt.
You cannot configure egress ACL support for remarked DSCP on tunnel interfaces.
Egress ACL support for remarked DSCP supports IP unicast traffic.
Egress ACL support for remarked DSCP is not relevant to multicast traffic. PFC QoS applies ingress
QoS changes to multicast traffic before applying egress QoS.
NetFlow and NetFlow data export (NDE) do not support interfaces where egress ACL support for
remarked DSCP is configured.
When egress ACL support for remarked DSCP is configured on any interface, you must configure
an interface-specific flowmask to enable NetFlow and NDE support on interfaces where egress ACL
support for remarked DSCP is not configured. Enter either the mls flow ip
interface-destination-source or the mls flow ip interface-full global configuration mode
command.
Interface counters are not accurate on interfaces where egress ACL support for remarked DSCP is
configured.
Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
PFC QoS Configuration Guidelines and Restrictions
38-39