Reconfiguring the 802.1p priority value currently assigned to a DSCP codepoint

To reconfigure the 802.1p priority value currently assigned to a DSCP codepoint, enter one of the following commands:

  • Global configuration context: 
    
qos dscp-map codepoint priority0 - 7
  • Policy configuration context: 
    
class [ipv4 | ipv6] {classname | action dscp | codepoint | priority | 0 - 7}
If you do not enter a priority value with the class action dscp command in a QoS policy, one of the following occurs:

  • The switch refers to the DSCP Policy table to assign the 802.1p value that is currently configured for the specified DSCP codepoint to remark matching packets.

  • If the specified DSCP codepoint is not associated with an 802.1p priority in the DSCP Policy table, an error message is displayed and the class action dscp codepoint command is not executed. You are prompted to reenter the command with an 802.1p priority: class action dscp codepoint priority 0 - 7 .

To ensure that the desired 802.1p priority is assigned to matching packets, you may need to first remap the priority to the new codepoint before you configure the policy, by using the qos dscp-map codepoint priority 0 - 7 command.

NOTE:
After you reconfigure the 802.1p priority for a DSCP codepoint, the switch immediately applies the new 802.1p priority value to packets transmitted with the associated codepoint as a result of:

  • Globally-configured QoS commands

  • class action dscp

    commands in other QoS policies

Applying classifier-based QoS policy to inbound traffic on VLAN

In the following example, a classifier-based QoS policy (dscp-remap) that assigns a new DSCP codepoint (af43) and associated 802.1p priority (5) to matching packets with a specified DSCP codepoint (af11) is applied to the inbound traffic on a VLAN. 
switch(config)# qos dscp-map af43 priority 5
switch(config)# class ipv4 dscp5
switch(config-class)# match ip any any dscp af11
switch(config-class)# exit
switch(config)# policy qos dscp-remap
switch(config-policy)# class ipv4 dscp5 action dscp af43
switch(config-policy)# exit
switch(config)# vlan 3 service-policy dscp-remap in
NOTE:

802.1p priority is mapped to the specified DSCP codepoint by using the qos dscp-map codepoint priority 0 - 7 command before the QoS policy is configured.