Addendum

wred weight
Configure the weight factor for computation of average-queue size. This weight value applies to front-
end ports. This mechanism to configure a weight for WRED and ECN functionality for front-end ports is
supported on the S6000 and Z9000 platforms.
S6000Z9000
Syntax
[no] wred weight number
Parameters
weight Define the weight factor to be used for computation of the
WRED average-queue size to either enable WRED to discard
packets or cause ECN to mark packets that exceed the
minimum threshold configured. This setting applies to front-
end ports only.
number Enter the weight as a number to be used to calculate the
average-queue size. The range is 1 to 15. The default is 0.
Default The default weight is zero.
Command
Modes
QOS-POLICY-OUT mode
Command
History
Version 9.3.0.0 Introduced on the S6000 and Z9000 platforms
Usage
Information
If the average queue size is more than the maximum threshold of WRED, the
packet is dropped. If the average queue size is between the minimum and
maximum threshold values, the decision to drop or queue the packet is taken
based on the packet drop probability. The probability that a packet is dropped
depends on the minimum threshold, maximum threshold, and mark probability
denominator.
Example
FTOS (conf-qos-policy-out) # wred weight 5
service-class wred
The mechanism to configure a weight factor for WRED and ECN functionality for backplane ports is
supported on the Z9000 platform. Also, this mechanism to configure a weight for WRED and ECN
functionality for front-end ports is supported on the Z9000 platforms. Create a weighted random early
detection (WRED) profile and ECN functionality per queue granularity for backplane ports, and attach the
WRED profile with a service class. You can enable or disable these parameters for each queue and specify
minimum and maximum buffer thresholds for each color-coding of the packets. Also, you can specify
the maximum drop rate percentage for yellow and green profiles. The per-queue profile configured is
applicable to all the backplane ports.
Z9000
Syntax
[No] service-class wred {green | weight | yellow} {[queue0
number/string] || [queue1 number/string] || [queue2 number/
Quality of Service (QoS)
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