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Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter 27 Configuring Quality of Service
Configuring QoS
Configuring the CoS Value for an Interface
QoS assigns the CoS value specified with this command to untagged frames from ingress interfaces
configured as trusted and to all frames from ingress interfaces configured as untrusted.
To configure the CoS value for an ingress interface, perform this task:
This example shows how to configure the CoS 5 as the default on Fast Ethernet interface 5/24:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface fastethernet 5/24
Switch(config-if)# qos cos 5
Switch(config-if)# end
Switch#
This example shows how to verify the configuration:
Switch# show qos interface fastethernet 5/24 | include Default COS
Default COS is 5
Switch#
Configuring DSCP Values for an Interface
QoS assigns the DSCP value specified with this command to non IPv4 frames received on interfaces
configured to trust DSCP and to all frames received on interfaces configured as untrusted.
To configure the DSCP value for an ingress interface, perform this task:
Command Purpose
Step 1
Switch(config)# interface {fastethernet |
gigabitethernet}
slot/interface
| Port-channel
number
}
Selects the interface to configure.
Step 2
Switch(config-if)# [no] qos cos
default_cos
Configures the ingress interface CoS value.
Use the no keyword to clear a configured value and
return to the default.
Step 3
Switch(config-if)# end
Exits configuration mode.
Step 4
Switch# show qos interface {fastethernet |
gigabitethernet}
slot/interface
Verifies the configuration.
Command Purpose
Step 1
Switch(config)# interface {fastethernet |
gigabitethernet}
slot/interface
| Port-channel
number
Selects the interface to configure.
Step 2
Switch(config-if)# [no] qos dscp
default_dscp
Configures the ingress interface DSCP value.
Use the no keyword to clear a configured value and
return to the default.
Step 3
Switch(config-if)# end
Exits configuration mode.
Step 4
Switch# show qos interface {fastethernet |
gigabitethernet}
slot/interface
Verifies the configuration.
