Administrator Guide

4 (100 b).
Dell(conf-qos-policy-in)#show config
!
qos-policy-input my-input-qos-policy
set ip-dscp 34
Dell(conf-qos-policy-in)#end
Dell#
Setting a dot1p Value for Egress Packets
To set a dot1p value for egress packets, use the following command.
• Set a dot1p value for egress packets.
QOS-POLICY-IN mode
set mac-dot1p
Creating an Output QoS Policy
To create an output QoS policy, use the following commands.
1. Create an output QoS policy.
CONFIGURATION mode
qos-policy-output
2. After you configure an output QoS policy, do one or more of the following:
Strict-Priority Queuing
Configuring Policy-Based Rate Shaping
Allocating Bandwidth to Queue
Specifying WRED Drop Precedence
Strict-Priority Queuing
You can configure strict-priority queueing in an output QoS policy. Strict-priority means that the system de-queues all packets from the
assigned queue before servicing any other queues.
Strict-priority queueing is performed using the Scheduler Strict feature. When scheduler strict is applied to multiple queues, the higher
queue number takes precedence. For more information, see Enabling Strict-Priority Queueing.
NOTE:
Strict priority on a a global level is not supported.
Configuring Policy-Based Rate Shaping
To configure policy-based rate-shaping, use the rate-shape command.
• Configure rate-shaping on egress traffic.
QOS-POLICY-OUT mode
rate-shape {kbps | pps} peak-rate {burst-kbps | burst-packets} [committed {kbps | pps}
committed-rate {burst-kbps | burst-packets}]
In a QoS output policy, you can configure rate-shaping on egress traffic:
• In either kilobits per second (kbps) or packets per second (pps)
• By specifying peak rate and the peak burst, and (optionally) committed rate and committed burst size
You must configure the peak rate and peak burst size using the same value: kilobits or packets per second. Similarly, you must configure
the committed rate and committed burst size with the same measurement.
Peak rate refers to the maximum rate for traffic arriving or exiting an interface under normal traffic conditions. Peak burst size indicates
the maximum size of unused peak bandwidth that is aggregated. This aggregated bandwidth enables brief durations of burst traffic that
exceeds the peak rate and committed burst.
Committed rate refers to the guaranteed bandwidth for traffic entering or leaving the interface under normal network conditions. When
traffic propagates at an average rate that is less than or equal to the committed rate, it is considered to be green-colored or coded. When
the transmitted traffic falls below the committed rate, the bandwidth, which is not used by any traffic that is traversing the network, is
aggregated to form the committed burst size. Traffic is considered to be green-colored up to the point at which the unused bandwidth
does not exceed the committed burst size.
Quality of Service (QoS)
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