Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 44 Configuring Quality of Service
Configuring VSS QoS
•
Specify the matching criteria used to define a traffic class.
• Create a traffic policy (policy map). The traffic policy defines the QoS policy actions to be taken for
each traffic class.
•
Apply the policy actions specified in the policy map to an interface, VLAN, or port and VLAN.
For more information about the MQC, see the “Modular Quality of Service Command-Line Interface”
section of the
Cisco IOS Quality of Service Solutions Configuration Guide, Release 12.3 .
Note
The incoming traffic is considered trusted by default. Only when the trusted boundary feature is enabled
on an interface can the port enter untrusted mode. In this mode, the switch marks the DSCP value of an
IP packet and the CoS value of the VLAN tag on the Ethernet frame as “0”.
Platform-supported Classification Criteria and QoS Features
The following table provides a summary of various classification criteria and actions supported on the
Catalyst 4500 series switch. For details, refer to the
Catalyst 4500 Series Switch Command Reference .
Supported classification actions Descriptions
match access-group Configures the match criteria for a class map on the basis of the specified ACL.
match any Configures the match criteria for a class map to be successful match criteria for all
packets.
match cos Matches a packet based on a Layer 2 class of service (CoS) marking.
match [ip] dscp Identifies a specific IP differentiated service code point (DSCP) value as a match
criterion. Up to eight DSCP values can be included in one match statement.
match [ip] precedence Identifies IP precedence values as match criteria.
match protocol Configures the match criteria for a class map on the basis of the specified protocol.
Supported Qos Features Descriptions
police Configures traffic policing.
police (percent) Configures traffic policing on the basis of a percentage of bandwidth available on an
interface.
police (two rates) Configures traffic policing using two rates, the committed information rate (CIR) and
the peak information rate (PIR).
set cos Sets the Layer 2 class of service (CoS) value of an outgoing packet.
set dscp Marks a packet by setting the differentiated services code point (DSCP) value in the
type of service (ToS) byte of IPv4 or traffic class byte of IPv6 packet.
set precedence Sets the precedence value in the packet header.
table map support Unconditional marking of one packet field based on another packet field.
priority Gives priority to a class of traffic belonging to a policy map.
shape Shapes traffic to the indicated bit rate according to the algorithm specified.
bandwidth Provides a guaranteed minimum bandwidth to each of the eight queues.
dbl Dynamic buffer limit.
queue-limit Specifies the maximum number of packets a transmit queue can hold.