Administrator Guide

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
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 Layer 3 egress traffic. The regulation mechanisms for output QoS policies are rate limiting, 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 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 DSCP Value for Egress Packets
Setting a dot1p Value for Egress Packets
Configuring Policy-Based Rate Policing
To configure policy-based rate policing, use the following command.
• Configure rate police ingress traffic.
QOS-POLICY-IN mode
rate-police
Setting a DSCP Value for Egress Packets
In an input QoS policy, you can set a DSCP value for egress packets based on ingress QoS classification.
The 6–bits that are used for DSCP are also used to identify the queue in which traffic is buffered. When you set a DSCP value, Dell
Networking OS displays an informational message advising you of the queue to which you should apply the QoS policy (using the
service-queue from POLICY-MAP-IN mode). If you apply the QoS policy to a queue other than the one specified in the informational
message, Dell Networking OS replaces the first 3–bits in the DSCP field with the queue ID you specified.
Dell#config
Dell(conf)#qos-policy-input my-input-qos-policy
Dell(conf-qos-policy-in)#set ip-dscp 34
% Info: To set the specified DSCP value 34 (100-010 b) the QoS policy must be mapped to queue
748
Quality of Service (QoS)