Quality of Service (QoS): Managing Bandwidth More Effectively

 

Using QoS Classifiers To Configure QoS for Outbound Traffic

 

 

N o t e

A codepoint must have an 802.1p priority assignment (0 - 7) before you can

 

configure that codepoint as a criteria for prioritizing packets by source-port.

 

If a codepoint shows No-overridein the Priority column of the DSCP Policy

 

Table (show qos dscp-map), then you must assign a 0 - 7 priority before

 

proceeding.

 

4. Configure the switch to assign the DSCP policy to packets from the

 

 

specified source-port.

 

Syntax: qos dscp-map < codepoint > priority < 0 - 7 >

 

This command is optional if a priority has already

 

been assigned to the < codepoint >. The command creates

 

a DSCP policy by assigning an 802.1p priority to a

 

specific DSCP. When the switch applies this priority to

 

a packet, the priority determines the packet’s queue in

 

the outbound port to which it is sent. If the packet leaves

 

the switch on a tagged port, it carries the 802.1p

 

priority with it to the next downstream device.

 

(Default: For most codepoints, No-override. See figure

 

11 on page 6-59on page 6-59.)

 

Syntax: interface < port-list> qos dscp < codepoint >

 

Assigns a DSCP policy to packets from the specified

 

source-port(s), and overwrites the DSCP in these

 

packets with the assigned < codepoint > value. This policy

 

includes an 802.1p priority and determines the

 

packet’s queue in the outbound port to which it is sent.

 

If the packet leaves the switch on a tagged port, it

 

carries the 802.1p priority with it to the next

 

downstream device. (Default: No-override)

 

no interface [e] < port-list> qos

 

Removes QoS classifier for the specified source-port(s).

 

show qos source-port

 

Displays a listing of all source-port QoS classifiers

 

currently in the running-config file.

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