Cisco Systems 3560 사용자 설명서

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Catalyst 3560 Switch Software Configuration Guide

OL-8553-06

Chapter 34 Configuring QoS

Configuring Standard QoS

Note

The egress queue default settings are suitable for most situations. You should change them only when
you have a thorough understanding of the egress queues and if these settings do not meet your QoS
solution.

Beginning in privileged EXEC mode, follow these steps to assign the shared weights and to enable
bandwidth sharing on the four egress queues mapped to a port. This procedure is optional.

To return to the default setting, use the no srr-queue bandwidth share interface configuration
command.

This example shows how to configure the weight ratio of the SRR scheduler running on an egress port.
Four queues are used, and the bandwidth ratio allocated for each queue in shared mode is 1/(1+2+3+4),
2/(1+2+3+4), 3/(1+2+3+4), and 4/(1+2+3+4), which is 10 percent, 20 percent, 30 percent, and 40
percent for queues 1, 2, 3, and 4. This means that queue 4 has four times the bandwidth of queue 1, twice
the bandwidth of queue 2, and one-and-a-third times the bandwidth of queue 3.

Switch(config)# interface gigabitethernet0/1

Switch(config-if)# srr-queue bandwidth share 1 2 3 4

Configuring the Egress Expedite Queue

You can ensure that certain packets have priority over all others by queuing them in the egress expedite
queue. SRR services this queue until it is empty before servicing the other queues.

Beginning in privileged EXEC mode, follow these steps to enable the egress expedite queue. This
procedure is optional.

Command

Purpose

Step 1

configure terminal

Enter global configuration mode.

Step 2

interface interface-id

Specify the port of the outbound traffic, and enter interface configuration
mode.

Step 3

srr-queue bandwidth share weight1
weight2 weight3 weight4

Assign SRR weights to the egress queues.

By default, all four weights are 25 (1/4 of the bandwidth is allocated to
each queue).

For weight1 weight2 weight3 weight4, enter the weights to control the
ratio of the frequency in which the SRR scheduler sends packets. Separate
each value with a space. The range is 1 to 255.

Step 4

end

Return to privileged EXEC mode.

Step 5

show mls qos interface interface-id
queueing

Verify your entries.

Step 6

copy running-config startup-config

(Optional) Save your entries in the configuration file.