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Cisco Systems IntelligentGigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide
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Chapter23 Configuring QoS
Configuring Auto-QoS
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 tha t 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.
Configuration Guidelines
Before configuring auto-QoS, you should be aware of this information:
•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 “Effects of
Auto-QoS on the Configuration” section on page 23-11.
•After auto-QoS is enabled, do not modify a pol icy map or aggregate policer that includes Auto QoS
in its name. If you need to modify the policy map or aggregate policer, make a copy of it, and change
the copied policy map or policer. To use the new policy map instead of the generated one, remove
the generated policy map from the interface, and apply the new policy map to it.
•You can enable auto-QoS on static, dynamic-access, voice VLAN access, and trunk ports.
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 the absence of a
Cisco IP Phone.
Switch(config-if)# mls qos trust device cisco-phone
The switch automatically assigns the egress queue usage (as
shown in Table23-3 on page 23-10) on this interface.
If some of your network traffic requires expedited forwarding,
configure queue 4 as the expedite queue. When the WRR
weight of a queue is set to 0, this queue becomes an expedite
queue. Only queue 4 can be the expedite queue.
The switch configures the CoS-to-egress-queue map:
•CoS values 0 and 1 select queue 1.
•CoS values 2 and 4 select queue 2.
•CoS values 3, 6, and 7 select queue 3.
•CoS value 5 selects queue 4.
Switch(config)# wrr-queue bandwidth 10 20 70 1
Switch(config)# no wrr-queue cos-map
Switch(config)# wrr-queue cos-map 1 0 1
Switch(config)# wrr-queue cos-map 2 2 4
Switch(config)# wrr-queue cos-map 3 3 6 7
Switch(config)# wrr-queue cos-map 4 5
Table23-4 Generated Auto-QoS Configuration (continued)
Description Automatically Generated QoS Command Equivalent