Setup Guide

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 congure rate-shaping on egress trac:
• 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 congure the peak rate and peak burst size using the same value: kilobits or packets per second. Similarly, you must congure the
committed rate and committed burst size with the same measurement.
Peak rate refers to the maximum rate for trac arriving or exiting an interface under normal trac conditions. Peak burst size indicates the
maximum size of unused peak bandwidth that is aggregated. This aggregated bandwidth enables brief durations of burst trac that
exceeds the peak rate and committed burst.
Committed rate refers to the guaranteed bandwidth for trac entering or leaving the interface under normal network conditions. When
trac 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 trac falls below the committed rate, the bandwidth, which is not used by any trac that is traversing the network, is
aggregated to form the committed burst size. Trac is considered to be green-colored up to the point at which the unused bandwidth
does not exceed the committed burst size.
Allocating Bandwidth to Queue
The switch schedules packets for egress based on Decit Round Robin (DRR). This strategy oers a guaranteed data rate.
Allocate bandwidth to queues only in terms of percentage in 4-queue and 8-queue systems. The following table shows the default
bandwidth percentage for each queue.
Table 82. Default Bandwidth Weights
Queue Default Bandwidth Percentage for 4–Queue
System
Default Bandwidth Percentage for 8–Queue
System
0 6.67% 1%
1 13.33% 2%
2 26.67% 3%
3 53.33% 4%
4 — 5%
5 — 10%
6 — 25%
7 — 50%
When you assign a percentage to one queue, note that this change also aects the amount of bandwidth that is allocated to other queues.
Therefore, whenever you are allocating bandwidth to one queue, Dell Networking recommends evaluating your bandwidth requirements for
all other queues as well.
• Allocate bandwidth to queues.
bandwidth-percentage
Assign each queue a bandwidth percentage ranging from 1 to 100%, in increments of 1%.
Specifying WRED Drop Precedence
You can congure the WRED drop precedence in an output QoS policy.
• Specify a WRED prole to yellow and/or green trac.
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Quality of Service (QoS)