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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 38 Configuring Standard QoS
How to Configure Standard QoS
Configuring SRR Shared Weights on Egress Queues
In shared mode, the queues share the bandwidth among them accord ing to the configured weights. The
bandwidth is guaranteed at this level but not limited to it. For example, if a queue empties and does not
require a share of the link, the remaining queues can expand into the unused bandwidth and share it
among them. With sharing, the ratio of the weights controls the frequency of dequeuing; the absolute
values are meaningless.
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.
Step 3 srr-queue bandwidth shape weight1
weight2 weight3 weight4
Assigns SRR weights to the egress queues.
By default, weig ht1 is set to 25; weight2, weight3, and weight4 are set to 0,
and these queues are in shared mode.
weight1 weight2 weight3 weight4—Enters the weights to control the
percentage of the port that is shaped. The inverse ratio (1/weight) controls
the shaping bandwidth for this queue. Separate each value with a space.
The range is 0 to 65535.
If you configure a weight of 0, the corresponding queue operates in shared
mode. The weight specified with the srr-queue bandwidth shape
command is ignored, and the weights specified with the srr-queue
bandwidth share interface configuration command for a queue come into
effect. When configuring queues in the same queue-set for both shap ing
and sharing, make sure that you configure the lowest number queue for
shaping.
The shaped mode overrides the shared mode.
Step 4 end Returns to privileged EXEC mode.
Command Purpose
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 interface interface-id Specifies the port of the outbound traffic, and enters interface
configuration mode.
Step 3 srr-queue bandwidth share weight1
weight2 weight3 weight4
Assigns SRR weights to the egress queues.
By default, all four weights are 25 (1/4 of the bandwidth is allocated to
each queue).
weight1 weight2 weight3 weight4—Enters the weights to cont rol 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 Returns to privileged EXEC mode.