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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 QoS on a Standalone Supervisor Engine 6-E/6L-E or Supervisor Engine 7-E/7L-E/8-E
Platform Hardware Capabilities
Prerequisites for Applying a QoS Service Policy
Unlike the Switch QoS model, there is no prerequisite for enabling QoS on various targets. Just the
attachment of a service policy enables QoS and detachment of that policy disables QoS on that target.
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.
set qos-group Sets a QoS group identifier (ID) that can be used later to classify packets.
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.
Qos Actions Numbers of entries supported
Classification 64k input and 64k output classification entries are supported.
A given policy can use at most 24k ACLs
Policing 16K policers are supported. Policers are allocated to given direction in blocks of 2k.
For example, 2k policers can be used in for input and 14k policers can be used for
output. Single rate policers uses one policer entry. Single Rate Three Color Marker
(srTCM) (RFC 2697) and Two Rate Three Color Marker (trTCM) (RFC 2698) uses
two policer entries
Marking Marking of Cos and DSCP/Precedence is supported through two marking tables, each
capable of supporting 512 entries. There are separate tables for each direction.
Queuing The queue size is Configurable with the maximum number of entries configurable per
port depending on the chassis and line card type.
DBL You can enable DBL action on all configured class-maps.
Supported classification actions Descriptions
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