Administrator Guide

DSCP/CP hex range
(XXX)xxx
DSCP Definition Traditional IP
Precedence
Internal Queue ID DSCP/CP decimal
100XXX AF4 (Assured
Forwarding)
Flash Override 2 32–47
011XXX AF3 Flash 1 16–31
010XXX AF2 Immediate 1 16–31
001XXX AF1 Priority 0 0–15
000XXX BE (Best Effort) Best Effort 0 0–15
• Enable the trust DSCP feature.
POLICY-MAP-IN mode
trust diffserv
Honoring dot1p Values on Ingress Packets
Dell EMC Networking OS honors dot1p values on ingress packets with the Trust dot1p feature.
The following table specifies the queue to which the classified traffic is sent based on the dot1p value.
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
Mapping dot1p Values to Service Queues
All traffic is by default mapped to the same queue, Queue 0.
If you honor dot1p on ingress, you can create service classes based the queueing strategy in Honoring dot1p Values on Ingress Packets.
You may apply this queuing strategy globally by entering the following command from CONFIGURATION mode.
• All dot1p traffic is mapped to Queue 0 unless you enable service-class dynamic dot1p on an interface or globally.
• Layer 2 or Layer 3 service policies supersede dot1p service classes.
• Create service classes.
INTERFACE mode
service-class dynamic dot1p
Guaranteeing Bandwidth to dot1p-Based Service Queues
To guarantee bandwidth to dot1p-based service queues, use the following command.
Apply this command in the same way as the bandwidth-percentage command in an output QoS policy (refer to Allocating Bandwidth
to Queue). The bandwidth-percentage command in QOS-POLICY-OUT mode supersedes the service-class bandwidth-
percentage command.
610
Quality of Service (QoS)