Concept Guide
The following example shows correct trac classications.
DellEMC#show cam layer3-qos interface tengigabitethernet 2/4
Cam Port Dscp Proto Tcp Src Dst SrcIp DstIp DSCP Queue
Index Flag Port Port Marking
-------------------------------------------------------------------------
20416 1 18 IP 0x0 0 0 23.64.0.5/32 0.0.0.0/0 20 2
20417 1 0 IP 0x0 0 0 23.64.0.2/32 0.0.0.0/0 10 1
20418 1 0 IP 0x0 0 0 23.64.0.3/32 0.0.0.0/0 12 1
20419 1 10 0 0x0 0 0 0.0.0.0/0 0.0.0.0/0 14 1
24511 1 0 0 0x0 0 0 0.0.0.0/0 0.0.0.0/0 - 0
Create a QoS Policy
There are two types of QoS policies — input and output.
Input QoS policies regulate Layer 3 and Layer 2 ingress trac. The regulation mechanisms for input QoS policies are rate policing and
setting priority values.
• Layer 3 — QoS input policies allow you to rate police and set a DSCP or dot1p value. In addition, you can congure a drop precedence
for incoming packets based on their DSCP value by using a DSCP color map. For more information, see DSCP Color Maps.
• Layer 2 — QoS input policies allow you to rate police and set a dot1p value.
Output QoS policies regulate egress trac. The regulation mechanisms for output QoS policies are bandwidth percentage, scheduler strict,
rate shaping and WRED.
NOTE
: When changing a "service-queue" conguration in a QoS policy map, all QoS rules are deleted and re-added automatically
to ensure that the order of the rules is maintained. As a result, the Matched Packets value shown in the show qos
statistics command is reset.
NOTE: To avoid issues misconguration causes, Dell EMC Networking recommends conguring either DCBX or Egress QoS
features, but not both simultaneously. If you enable both DCBX and Egress QoS at the same time, the DCBX conguration is
applied and unexpected behavior occurs on the Egress QoS.
Creating an Input QoS Policy
To create an input QoS policy, use the following steps.
1 Create a Layer 3 input QoS policy.
CONFIGURATION mode
qos-policy-input
Create a Layer 2 input QoS policy by specifying the keyword layer2 after the qos-policy-input command.
2 After you create an input QoS policy, do one or more of the following:
Conguring Policy-Based Rate Policing
Setting a dot1p Value for Egress Packets
Conguring Policy-Based Rate Policing
To congure policy-based rate policing, use the following command.
• Congure rate police ingress trac.
QOS-POLICY-IN mode
rate-police
Quality of Service (QoS)
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