Configuring a DSCP-to-traffic class and drop precedence mutation map

Follow these steps to configure a QoS DSCP to traffic class and drop precedence mutation map.

Procedure

  1. Enter global configuration mode.
    device# configure terminal
    
  2. Create and name a QoS DSCP-to-traffic class and drop precedence mutation map.
    device(config)# qos map dscp-traffic-class dscpTcDpMap
    
  3. Define the QoS DSCP-to-traffic class and drop precedence values.
    device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 10 to traffic-class 3 drop-precedence 1
    device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 40 to traffic-class 4 drop-precedence 1
    device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 45 to traffic-class 5 drop-precedence 0
    device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 52 to traffic-class 3 drop-precedence 1
    
    If a default DSCP-to-traffic class map is not defined, then the IP precedence bits (first 3 bits) of the DSCP are used as the traffic class for the map, and drop precedence is given a value of 0.
  4. Return to privileged exec mode.
    device(config-dscp-traffic-class-dscpTcDpMap)# end
    
  5. Verify the configuration.
    device# show qos maps dscp-traffic-class 
    DSCP-to-TC Map: a1 (x/y: TC = x, DP = y, DSCP = d1d2)
        d1 :  d2  0   1   2   3   4   5   6   7   8   9 
        ------------------------------------------------
         0 :     0/0 0/0 0/0 0/0 0/0 0/0 0/0 0/0 1/0 1/0
         1 :     1/0 1/0 1/0 1/0 1/0 1/0 2/0 2/0 2/0 2/0
         2 :     2/0 2/0 2/0 2/0 3/0 3/0 3/0 3/0 3/0 3/0
         3 :     3/0 3/0 4/0 4/0 4/0 4/0 4/0 4/0 4/0 4/0
         4 :     5/0 5/0 5/0 5/0 5/0 5/0 5/0 5/0 6/0 6/0
         5 :     6/0 6/0 6/0 6/0 6/0 6/0 7/0 7/0 7/0 7/0
         6 :     7/0 7/0 7/0 7/0
    
        Enabled on the following interfaces: >>> map a1 is not applied on any interface.
    
    CoS = Class of Service, TC = Traffic Class, DP = Drop Precedence.
  6. Save the running-config file to the startup-config file
    device# copy running-config startup-config
    

QoS DSCP to traffic class and drop precedence mutation map configuration example

device# configure terminal
device(config)# qos map dscp-traffic-class dscpTcDpMap
device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 10 to traffic-class 3 drop-precedence 1
device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 40 to traffic-class 4 drop-precedence 1
device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 45 to traffic-class 5 drop-precedence 0
device(config-dscp-traffic-class-dscpTcMap)# map dscp-value 52 to traffic-class 3 drop-precedence 1
device(dscp-traffic-class-dscpTcDpMap)# end
device# show qos maps dscp-traffic-class dscpTcDpMap
device# copy running-config startup-config