Quality of Service (QoS): Managing Bandwidth More Effectively

Using QoS Classifiers To Configure Quality of Service for Outbound Traffic

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 in a tagged VLAN, it carries the 802.1p priority with it to the next downstream device. (Default: For most codepoints, No-override. See figure 15-8on page 15-52.)

Syntax: interface [ e ] < port-list> qos dscp < codepoint >

Assigns a DSCP policy to packets from the specified source-port(s), and overwrites the DSCP in these pack­ ets 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 in a tagged VLAN, 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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