Configure a CoS-to-traffic Class Mutation Map

If a CoS-to-traffic class mutation map is not defined, the default CoS is used as value of the traffic class, and 0 is used for the drop precedence. For Extreme 8720, Extreme 8520, SLX 9250, and SLX 9150 platforms, the supported drop precedence are 0, 1, and 2.

Enter global configuration mode.
```
device# configure terminal
```

Create and name a CoS-to-traffic class map.

device(config)# qos map cos-traffic-class cosTCMap

Map ingress CoS value to the CoS-to-traffic class map traffic-class and drop precedence values.

device(config-cos-traffic-class-cosTCMap)# map cos 4 to traffic-class 3 drop-precedence 0
device(config-cos-traffic-class-cosTCMap)# map cos 5 to traffic-class 5 drop-precedence 1
device(config-cos-traffic-class-cosTCMap)# map cos 6 to traffic-class 6 drop-precedence 0
device(config-cos-traffic-class-cosTCMap)# map cos 7 to traffic-class 6 drop-precedence 1

The drop-precedence parameter is mandatory.

Return to privileged EXEC mode.

device(config-cos-traffic-class-cosTCMap)# end

Verify the configuration.

device# show qos maps cos-traffic-class 

Cos-to-Traffic Class map 'cosTCMap'
         In-Cos  : 0  1  2  3  4  5  6  7
   --------------------------------------
   TrafficClass  : 0  1  2  3  3  6  6  6
   DropPrecedence: 0  0  0  0  0  1  0  1

The following example summarizes the commands in this procedure.

device# configure terminal
device(config)# qos map cos-traffic-class cosTCMap
device(config-cos-traffic-class-cosTCMap)# map cos 4 to traffic-class 3 drop-precedence 0
device(config-cos-traffic-class-cosTCMap)# map cos 5 to traffic-class 5 drop-precedence 1
device(config-cos-traffic-class-cosTCMap)# map cos 6 to traffic-class 6 drop-precedence 0
device(config-cos-traffic-class-cosTCMap)# map cos 7 to traffic-class 6 drop-precedence 1 
device(config-cos-traffic-class-cosTCMap)# end
device# show qos maps cos-traffic-class