Cisco IE 4000, Руководство по настройке программного обеспечения

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Configuring QoS
Configuring QoS

You cannot configure more than two unique threshold values for the WTD qualifiers ( cos , dscp , precedence , or
qos-group ) in the queue-limit command. However, there is no limit to the number of qualifiers that you can map to
those thresholds. You can configure a third unique threshold value to set the maximum queue, using the queue-limit
command with no qualifiers.

A WTD qualifier in the queue-limit command must be the same as at least one match qualifier in the associated
class map.

In an output policy map, when you configure a queue-limit for a unique class, all other output policy maps must use
the same format of qualifier type and qualifier value. Only queue-limit threshold values can be different. For example,
when you configure class A queue-limit thresholds for
dscp 30 and dscp 50 in policy-map1 , and you configure class
A queue-limits in policy-map 2, you must use dscp 30 and dscp 50 as qualifiers. You cannot use dscp 20 and dscp
40 . The threshold values can be different, but different threshold values would create a new unique queue-limit
configuration.
Beginning in privileged EXEC mode, follow these steps to use WTD to adjust the queue size for a traffic class:
Command Purpose
1. configure terminal Enter global configuration mode.
2. policy-map policy-map-name Create a policy map by entering the policy map name, and enter
policy-map configuration mode.
3. class { class-map-name | class-default } Enter a child class-map name, or class-default to match all
unclassified packets, and enter policy-map class configuration
mode.

If you enter a class-map name, you must perform Step 4 to
configure a scheduling action (
bandwidth , shape average ,
or priority) before you go to Step 5 to configure queue-limit.

If you enter class-default, you can skip Step 4.
4. bandwidth { rate | percent value | remaining
percent value }
or
shape average target bps
or
priority
Configure a scheduling action for the traffic class. For more
information, see
Configuring Output Policy Maps with
Class-Based-Weighted-Queuing, page 630 , Configuring Output
Policy Maps with Class-Based Shaping, page 631 , Configuring
Output Policy Maps with Port Shaping, page 632 , or Configuring
Output Policy Maps with Class-Based Priority Queuing,
page 633
.