Traffic Shaping - Cisco Nexus 9000 Series Configuration Manual

Configuring Queuing and Scheduling
• If no AFD policy has already been applied in system QoS—then you can configure the same AFD policy
WRED and AFD Differences
Although WRED and AFD are both AQM algorithms, they have different approaches to help manage
congestion:
• WRED computes a random drop probability and drops the packets indiscriminately across all the flows
• AFD computes drop probability based on the arrival rate of incoming flows, compares it with the computed
Note
AFD and WRED cannot be applied at the same time. Only one can be used in a system.

Traffic Shaping

Traffic shaping allows you to control the traffic going out of an interface in order to match its flow to the
speed of the remote target interface and to ensure that the traffic conforms to policies contracted for it. You
can shape traffic that adheres to a particular profile to meet downstream requirements. Traffic shaping eliminates
bottlenecks in topologies with data-rate mismatches.
switch(config-if)#service-policy type queuing output LM-out-100G
switch(config)# interface ethernet 1/52
switch(config-if)# service-policy type queuing output LM-out-100G
Unable to perform the action due to incompatibility:
profiles reached for unique values of queue management parameters (alpha, beta,
max-threshold) in AFD config"
on ports on a different slice, or configure different AFD policies on ports in the same slice.
Note You cannot configure an AFD queuing in the System QoS at a later time.
The following is an example of the system error when AFD queuing is already configured in the system:
interface Ethernet1/50
service-policy type queuing output LM-out-40G
interface Ethernet1/51
service-policy type queuing output LM-out-40G
interface Ethernet1/52
service-policy type queuing output LM-out-100G
interface Ethernet1/53
service-policy type queuing output LM-out-100G
interface Ethernet1/54
service-policy type queuing output LM-out-100G
(config-sys-qos)# service-policy type queuing output LM-out
Unable to perform the action due to incompatibility:
profiles reached for unique values of queue management parameters (alpha, beta,
max-threshold) in AFD config"
in a class of traffic.
fair rate, and drops the packets from the elephant flows while not impacting the mice flows.
Cisco Nexus 9000 Series NX-OS Quality of Service Configuration Guide, Release 7.x
Traffic Shaping
Module 1 returned status "Max
Module 1 returned status "Max
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