Assigning DSCP policies to packets matching specified global classifiers

Assigning the following DSCP policies to the packets that match the specified global IP-device classifiers:

IP address

DSCP Policy

DSCP codepoint

802.1p priority













  1. Determine whether the DSCP codepoints that you want to use to mark matching packets already have an 802.1p priority assigned, which could indicate use by existing applications (show qos dscp-map command). This is not a problem if the configured priorities are acceptable for all applications that use the same DSCP.

    Note that a DSCP codepoint must have an associated priority before you can use it to mark matching packets.

    Display the current DSCP-map configuration
  2. Configure the priorities for the DSCPs you want to use to mark packets.
    Assigning 802.1p priorities to the selected DSCPs
  3. Assign the DSCP policies to the specified IP-device addresses and display the result.
    switch(config)# qos device-priority dscp 000111
    switch(config)# qos device-priority dscp 000101
    switch(config)# qos device-priority ipv4 dscp 000010
    switch(config)# qos device-priority 2001:db8:2:1:212:79ff:fe88:a100 dscp 000
    switch(config)# qos device-priority ipv6 2001:db8:3:3/64 dscp 000010
    switch(config)# show qos device-priority
      Device priorities
      Device Address                                Apply rule | DSCP  Priority
      --------------------------------------------  ---------- + ------ -----------                                     Priority  | 000111 7                                   Priority  | 000101 5                                Priority  | 000010 1
      2001:db8:2:1:212:79ff:fe88:a100                Priority  | 000101 3
      2001:db8:3:3/64                                Priority  | 000010 1

The switch applies the DSCP policies (as shown in the figure in step 2), to IP packets with the specified IP addresses and subnet masks (source or destination) received in the switch. The switch manages the packets as follows:
  • Overwrites the original DSCPs in the selected packets with the new DSCPs specified in the above policies.

  • Assigns the 802.1p priorities in the above policies to the appropriate packets.