Configuring Auto-Qos; Generated Auto-Qos Configuration - Cisco Catalyst 2975 Software Configuration Manual

Configuring Auto-QoS

Configuring Auto-QoS
You can use the auto-QoS feature to simplify the deployment of QoS features. Auto-QoS determines the
network design and enables QoS configurations so that the switch can prioritize different traffic flows.
It uses the ingress and egress queues instead of using the default (disabled) QoS behavior. The switch
offers best-effort service to each packet, regardless of the packet contents or size, and sends it from a
single queue.
When you enable auto-QoS, it automatically classifies traffic based on the traffic type and ingress packet
label. The switch uses the classification results to choose the appropriate egress queue.
You use auto-QoS commands to identify ports connected to these Cisco devices:
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You also use the commands to identify ports that receive trusted traffic through an uplink. Auto-QoS then
performs these functions:
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These sections contain this configuration information:
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Generated Auto-QoS Configuration

By default, auto-QoS is disabled on all ports. Packets are not modified--the CoS, DSCP and IP
precedence values in the packet are not changed.
When you enable the auto-QoS feature on the first port of the interface:
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Catalyst 2975 Switch Software Configuration Guide
33-20
Cisco IP Phones
Devices running the Cisco SoftPhone application
Cisco TelePresence
Cisco IP Camera
Detects the presence or absence of auto-QoS devices through conditional trusted interfaces.
Configures QoS classification
Configures egress queues
Generated Auto-QoS Configuration, page 33-20
Effects of Auto-QoS on the Configuration, page 33-30
Auto-QoS Configuration Guidelines, page 33-30
Enabling Auto-QoS, page 33-31
Ingress packet label is used to categorize traffic, to assign packet labels, and to configure the ingress
and egress queues.
QoS is globally enabled (mls qos global configuration command), and other global configuration
commands are automatically generated. (See
Switch enables the trusted boundary feature and uses the Cisco Discovery Protocol (CDP) to detect
the presence of a supported device.
Policing is used to determine whether a packet is in or out of profile and specifies the action on the
packet.
Table 33-5.)
Chapter 33 Configuring QoS
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