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Is IP CEF ECMP with include-port still happening in HW?

Hi all

 

Would anyone from Cisco be able to confirm if IP CEF ECMP happens in hardware (on Cat9k and Cat3850) when include-port algortihm is configured?

 

ip cef load-sharing algorithm include-ports source

 

In my understanding this is critical for VXLAN deployments as ECMP is only effective if based on SOURCE UDP port, but even the latest IOS-XE configuration guides state the following:

 

======

**** The Layer 4 load-balancing algorithm applies to software switched packets. ****

For platforms that switch traffic using a hardware forwarding engine, the hardware load-balancing decision might be different from the software load-balancing decision for the same traffic stream. You might want to override the configured algorithm.

=====

 

This quote is from here: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipswitch_cef/configuration/xe-16-8/isw-cef-xe-16-8-book/isw-cef-load-balancing.html

 

So, how do I read it? Does it mean that Layer 4 ECMP IS ALWAYS unconditionally applied to process switched; but command above is required to make sure hardware switched packets are also switched using Layer 4 ECMP? Or does it say that if I enable 'include-port' my algorithm becomes process switched? (I feel this is not right, but would rather confirm)

 

Many thanks

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