Effects Of Auto-Qos On The Configuration; Auto-Qos Configuration Guidelines - Cisco WS-C3560-48PS-S Software Configuration Manual

Configuring Auto-QoS
Table 28-5 Generated Auto-QoS Configuration (continued)
Description
The switch automatically sets the ingress classification to trust
the CoS value received in the packet on a nonrouted port or to
trust the DSCP value received in the packet on a routed port.
If you entered the auto qos voip cisco-phone command, the
switch automatically enables the trusted boundary feature,
which uses the CDP to detect the presence or absence of a
Cisco IP Phone.

Effects of Auto-QoS on the Configuration

When auto-QoS is enabled, the auto qos voip interface configuration command and the generated
configuration are added to the running configuration.
The switch applies the auto-QoS-generated commands as if the commands were entered from the CLI.
An existing user configuration can cause the application of the generated commands to fail or to be
overridden by the generated commands. These actions occur without warning. If all the generated
commands are successfully applied, any user-entered configuration that was not overridden remains in
the running configuration. Any user-entered configuration that was overridden can be retrieved by
reloading the switch without saving the current configuration to memory. If the generated commands fail
to be applied, the previous running configuration is restored.

Auto-QoS Configuration Guidelines

Before configuring auto-QoS, you should be aware of this information:
•
•
•
•
•
Catalyst 3560 Switch Software Configuration Guide
28-22
In this release, auto-QoS configures the switch only for VoIP with Cisco IP Phones.
To take advantage of the auto-QoS defaults, you should enable auto-QoS before you configure other
QoS commands. If necessary, you can fine-tune the QoS configuration, but we recommend that you
do so only after the auto-QoS configuration is completed. For more information, see the
Auto-QoS on the Configuration" section on page
You can enable auto-QoS on static, dynamic-access, voice VLAN access, and trunk ports.
By default, the CDP is enabled on all ports. For auto-QoS to function properly, do not disable the
CDP.
Policing is not enabled with auto-QoS. You can manually enable policing, as described in the
"Configuring a QoS Policy" section on page
Automatically Generated Command
Switch(config-if)# mls qos trust cos
Switch(config-if)# mls qos trust dscp
Switch(config-if)# mls qos trust device cisco-phone
28-22.
28-36.
Chapter 28 Configuring QoS
"Effects of
78-16156-01