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IBM 12.1(22)EA6 User Manual

Page 418

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23-10

Cisco Systems Intelligent Gigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide

24R9746

Chapter 23 Configuring QoS

Configuring Auto-QoS

Table 23-3

lists the generated auto-QoS configuration for the egress queues.

When you enable the auto-QoS feature on the first interface, these automatic actions occur:

When you enter the auto qos voip cisco-phone interface configuration command on a port at the
edge of a 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 interface 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 egress queues on
the port according to the settings in

Table 23-3

.

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 in ingress packets (the assumption is that
traffic has already been classified by other edge devices). The switch configures egress queues on
the port according to the settings in

Table 23-3

.

For information about the trusted boundary feature, see the

“Configuring Trusted Boundary” section

on page 23-20

.

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 ingress packet label and applies the commands listed in

Table 23-4

to the interface.

Table 23-3

Auto-QoS Configuration for the Egress Queues

Egress Queue

Queue Number

CoS-to-Queue Map

Queue Weight

1% WRR

4

5

1 percent

70% WRR

3

3, 6, 7

70 percent

20% WRR

2

2, 4

20 percent

10% WRR

1

0,1

10 percent

Table 23-4

Generated Auto-QoS Configuration

Description

Automatically Generated QoS Command Equivalent

The switch automatically enables standard QoS and configures
the CoS-to-DSCP map (maps CoS values in incoming packets
to a DSCP value) as shown in

Table 23-2 on page 23-9

.

Switch(config)# mls qos map cos-dscp 0 8 16 26 32 46

48 56

If you entered the auto qos voip trust command, the switch
automatically sets the ingress classification on the interface to
trust the CoS value in the packet.

Switch(config-if)# mls qos trust cos