Administrator Guide

ip access-list extended AF1-FB1
seq 5 permit ip host 23.64.0.2 any
seq 10 deny ip any any
!
ip access-list extended AF1-FB2
seq 5 permit ip host 23.64.0.3 any
seq 10 deny ip any any
!
ip access-list extended AF2
seq 5 permit ip host 23.64.0.5 any
seq 10 deny ip any any
In the previous example, the ClassAF1 does not classify traffic as intended. Traffic matching the first match criteria is classified
to Queue 1, but all other traffic is classified to Queue 0 as a result of CAM entry 20419.
When you remove the explicit “deny any” rule from all three ACLs, the CAM reflects exactly the desired classification.
The following example shows correct traffic classifications.
DellEMC#show cam layer3-qos interface gigabitethernet 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 traffic. 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 configure 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 traffic. The regulation mechanisms for output QoS policies are bandwidth percentage,
scheduler strict, rate shaping and WRED.
NOTE:
When changing a "service-queue" configuration 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 misconfiguration causes, Dell EMC Networking recommends configuring either DCBX or Egress QoS
features, but not both simultaneously. If you enable both DCBX and Egress QoS at the same time, the DCBX configuration
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:
Configuring Policy-Based Rate Policing
Setting a dot1p Value for Egress Packets
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Quality of Service (QoS)