The Cisco Modular
QoS CLI (MQC) provides a standard set of commands for configuring QoS.
You can use MQC to
define additional traffic classes and to configure QoS policies for the whole
system and for individual interfaces. Configuring a QoS policy with MQC
consists of the following steps:
- Define traffic classes.
- Associate policies and
actions with each traffic class.
- Attach policies to logical or
physical interfaces as well as at the global system level.
MQC provides two
command types to define traffic classes and policies:
class map that represents a class of traffic based on packet-matching criteria.
Class maps are referenced in policy maps.
The class map
classifies incoming packets based on matching criteria, such as the IEEE 802.1p
class of service (CoS) value. Unicast and multicast packets are classified.
Defines a policy map
that represents a set of policies to be applied on a class-by-class basis to
The policy map
defines a set of actions to take on the associated traffic class, such as
limiting the bandwidth or dropping packets.
You define the
policy-map object types when you create them:
objects that you can use for system level related actions.
objects that you can use for classification.
objects that you can use for queuing and scheduling.
qos type is the default for the
policy-map commands, but not for the
service-policy which requires that you specify an
You can attach
policies to interfaces or EtherChannels as well as at the global system level
by using the
You can view all or
individual values for MQC objects by using the
An MQC target is an
entity (such as an Ethernet interface) that represents a flow of packets. A
service policy associates a policy map with an MQC target and specifies whether
to apply the policy on incoming or outgoing packets. This mapping enables the
configuration of QoS policies such as marking, bandwidth allocation, buffer
allocation, and so on.