Dell S4820T Configuration Manual page 801

Create a Layer 2 input policy map by specifying the keyword layer2 with the policy-map-input
command.
2. After you create an input policy map, do one or more of the following:
Applying a Class-Map or Input QoS Policy to a Queue
Applying an Input QoS Policy to an Input Policy Map
Honoring DSCP Values on Ingress Packets
Honoring dot1p Values on Ingress Packets
3. Apply the input policy map to an interface.
Applying a Class-Map or Input QoS Policy to a Queue
To apply a class-map or input QoS policy to a queue, use the following command.
• Assign an input QoS policy to a queue.
POLICY-MAP-IN mode
service-queue
Applying an Input QoS Policy to an Input Policy Map
To apply an input QoS policy to an input policy map, use the following command.
• Apply an input QoS policy to an input policy map.
POLICY-MAP-IN mode
policy-service-queue <number> qos-polcy
Honoring DSCP Values on Ingress Packets
Dell Networking OS provides the ability to honor DSCP values on ingress packets using Trust DSCP
feature.
The following table lists the standard DSCP definitions and indicates to which queues Dell Networking OS
maps DSCP values. When you configure trust DSCP, the matched packets and matched bytes counters
are not incremented in the show qos statistics.
Table 61. Default DSCP to Queue Mapping
DSCP/CP hex DSCP Definition
range (XXX)xxx
111XXX
110XXX
101XXX EF (Expedited
Forwarding)
100XXX AF4 (Assured
Forwarding)
011XXX AF3
Quality of Service (QoS)
Traditional IP Internal Queue ID
Precedence
Network Control 3
Internetwork 3
Control
CRITIC/ECP 2
Flash Override 2
Flash 1
DSCP/CP decimal
48–63
48–63
32–47
32–47
16–31
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