Mls Qos Cos - Cisco Catalyst 3750 Command Reference Manual

Hide thumbs Also See for Catalyst 3750:

Table of Contents

Catalyst 3750 Switch Cisco IOS Commands

mls qos cos

Use the mls qos cos interface configuration command on the switch stack or on a standalone switch to

define the default class of service (CoS) value of a port or to assign the default CoS to all incoming

packets on the port. Use the no form of this command to return to the default setting.

Syntax Description

The default CoS value for a port is 0.

CoS override is disabled.

Command Modes

Interface configuration

Command History

Usage Guidelines

You can use the default value to assign a CoS and Differentiated Services Code Point (DSCP) value to

all incoming packets that are untagged (if the incoming packet does not have a CoS value). You also can

assign a default CoS and DSCP value to all incoming packets by using the override keyword.

Use the override keyword when all incoming packets on certain ports deserve higher or lower priority

than packets entering from other ports. Even if a port is previously set to trust DSCP, CoS, or IP

precedence, this command overrides the previously configured trust state, and all the incoming CoS

values are assigned the default CoS value configured with the mls qos cos command. If an incoming

packet is tagged, the CoS value of the packet is modified with the default CoS of the port at the ingress

This example shows how to configure the default port CoS to 4 on a port:

Switch(config)# interface gigabitethernet2/0/1

Switch(config-if)# mls qos trust cos

Switch(config-if)# mls qos cos 4

mls qos cos {default-cos | override}

no mls qos cos {default-cos | override}

Assign a default CoS value to a port. If packets are untagged, the default CoS value

becomes the packet CoS value. The CoS range is 0 to 7.

Override the CoS of the incoming packets, and apply the default CoS value on the

port to all incoming packets.

Modification

This command was introduced.

Catalyst 3750 Switch Command Reference