Cisco Catalyst 3750 Software Configuration Manual page 511

Chapter 26 Configuring QoS
When you enable the auto-QoS feature on the first port, these automatic actions occur:
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•
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When you enable auto-QoS by using the auto qos voip cisco-phone or the auto qos voip trust interface
configuration command, the switch automatically generates a QoS configuration based on the traffic
type and the ingress packet label and applies the commands listed in
Note On an ES port, the srr-queue bandwidth shape interface configuration command is not part of the
generated auto qos voip command list.
Table 26-5 Generated Auto-QoS Configuration
Description
The switch automatically enables standard QoS and configures
the CoS-to-DSCP map (maps CoS values in inbound packets to
a DSCP value).
The switch automatically maps CoS values to an ingress queue
and to a threshold ID.
The switch automatically maps CoS values to an egress queue
in the queue-set and to a threshold ID.
78-15870-01
QoS is globally enabled (mls qos global configuration command), and other global configuration
commands are added.
When you enter the auto qos voip cisco-phone interface configuration command on a port at the
edge of the network that is connected to a Cisco IP phone, the switch enables the trusted boundary
feature. The switch uses the Cisco Discovery Protocol (CDP) to detect the presence or absence of a
Cisco IP phone. When a Cisco IP phone is detected, the ingress classification on the port is set to
trust the QoS label received in the packet. When a Cisco IP phone is absent, the ingress classification
is set to not trust the QoS label in the packet. The switch configures ingress queues and the egress
queue-set on the port according to the settings in
When you enter the auto qos voip trust interface configuration command on a port connected to the
interior of the network, the switch trusts the CoS value for nonrouted ports or the DSCP value for
routed ports in ingress packets (the assumption is that traffic has already been classified by other
edge devices). The switch configures the ingress queues and the egress queue-set on the port
according to the settings in
For information about the trusted boundary feature, see the
Ensure Port Security" section on page
Table 26-3
Table 26-3 and Table 26-4.
26-46.
Automatically Generated Command
Switch(config)# mls qos
Switch(config)# mls qos map cos-dscp 0 8 16 26 32 46
48 56
Switch(config)# no mls qos srr-queue input cos-map
Switch(config)# mls qos srr-queue input cos-map
queue 1 threshold 3 0
Switch(config)# mls qos srr-queue input cos-map
queue 1 threshold 2 1
Switch(config)# mls qos srr-queue input cos-map
queue 2 threshold 1 2
Switch(config)# mls qos srr-queue input cos-map
queue 2 threshold 2 4 6 7
Switch(config)# mls qos srr-queue input cos-map
queue 2 threshold 3 3 5
Switch(config)# no mls qos srr-queue output cos-map
Switch(config)# mls qos srr-queue output cos-map
queue 1 threshold 3 5
Switch(config)# mls qos srr-queue output cos-map
queue 2 threshold 3 3 6 7
Switch(config)# mls qos srr-queue output cos-map
queue 3 threshold 3 2 4
Switch(config)# mls qos srr-queue output cos-map
queue 4 threshold 2 1
Switch(config)# mls qos srr-queue output cos-map
queue 4 threshold 3 0
Catalyst 3750 Metro Switch Software Configuration Guide
Configuring Auto-QoS
and Table 26-4.
"Configuring a Trusted Boundary to
Table 26-5 to the port.
26-31