Chapter 2
Catalyst 2960 Switch Cisco IOS Commands
mls qos cos
Use the mls qos cos interface configuration command 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
default-cos
override
Defaults
The default CoS value for a port is 0.
CoS override is disabled.
Command Modes
Interface configuration
Command History
Release
12.2(25)FX
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 port.
Examples
This example shows how to configure the default port CoS to 4 on a port:
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# mls qos trust cos
Switch(config-if)# mls qos cos 4
78-16882-01
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 2960 Switch Command Reference
mls qos cos
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