Concept Guide

Table 61. Default dot1p to Queue Mapping
dot1p Queue ID
0 0
1 0
2 0
3 1
4 2
5 3
6 3
7 3
The dot1p value is also honored for frames on the default VLAN. For more information, refer to Priority-Tagged Frames on the Default
VLAN.
• Enable the trust dot1p feature.
POLICY-MAP-IN mode
trust dot1p
Enabling Fall Back to Trust Diserve or dot1p
When using QoS service policies with multiple class maps, you can congure the Dell Networking OS to use the incoming DSCP or dot1p
marking as a secondary option for packet queuing if no match occurs in the class maps.
When you use class-maps, trac is matched against each class-map sequentially from rst to last. The sequence is based on the priority of
the rules, as follows:
1 Rules with lowest priority, or in the absence of a priority conguration.
2 Rules of the next numerically higher queue.
By default, if no match occurs, the packet is queued to the default queue, Queue 0.
In the following conguration, packets are classied to queues using three class maps:
Example of Viewing Packet Classes Based on DSCP Value
!
policy-map-input input-policy
service-queue 1 class-map qos-BE1
service-queue 3 class-map qos-AF3
service-queue 4 class-map qos-AF4
trust diffserv fallback
!
class-map match-any qos-AF3
match ip dscp 24
match ip access-group qos-AF3-ACL
!
class-map match-any qos-AF4
match ip dscp 32
match ip access-group qos-AF4-ACL
!
class-map match-all qos-BE1
match ip dscp 0
match ip access-group qos-BE1-ACL
The packet classication logic for the conguration shown is as follows:
Quality of Service (QoS)
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