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Quality of Service (QoS)
Dell Networking OS supports quality of service (QoS).
Differentiated service is accomplished by classifying and queuing traffic, and assigning priorities to those queues.
The switch traffic has four data queues per port. All queues are serviced using the Weighted Round Robin scheduling algorithm.
You can only manage prioritize queuing on egress.
NOTE: When you enable DCB, the egress QoS features in the output QoS policy-map (such as service-class bandwidth-
percentage and bandwidth-percentage), the default bandwidth allocation ratio for egress queues and strict-priority may not
work as intended.This is to provide compatibility with DCBX. Hence, it is recommended to have the DCB disabled when you
wish to apply these features exclusively.
Table 58. Dell Networking OS Support for Port-Based, Policy-Based, and Multicast QoS Features
Feature Direction
Port-Based QoS Configurations Ingress + Egress
Set dot1p Priorities for Incoming Traffic Ingress
Honor dot1p Priorities on Ingress Traffic Ingress
Configure Port-based Rate Policing Ingress
Configure Port-based Rate Shaping Egress
Policy-Based QoS Configurations Ingress + Egress
Classify Traffic Ingress
Create a Layer 3 Class Map Ingress
Set DSCP Values for Egress Packets Based on Flow Ingress
Create a Layer 2 Class Map Ingress
Create a QoS Policy Ingress + Egress
Create an Input QoS Policy Ingress
Configure Policy-Based Rate Policing Ingress
Set a DSCP Value for Egress Packets Ingress
Set a dot1p Value for Egress Packets Ingress
Create an Output QoS Policy Egress
Configure Policy-Based Rate Shaping Egress
Allocate Bandwidth to the Queue Egress
Configure a Scheduler to Queue Egress
Specify WRED Drop Precedence Egress
Create Policy Maps Ingress + Egress
Create Input Policy Maps Ingress
Honor DSCP Values on Ingress Packets Ingress
Honoring dot1p Values on Ingress Packets Ingress
Create Output Policy Maps Egress
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