ACI QoS Marking EPG & L3Out

This video provides details about QoS marking configuration on EPG and L3Out

[@SujayRokade]

Hey SR, I have a QOS related doubt.
Connectivity:
Router 1 -- L3Out1 ACI Contract L3Out2 -- Router 2
Ques 1: What is the difference between applying QOS on Contract vs applying QOS on L3OUTs?
Ques 2: I have QOS applied only on L3out1 wherein I have defined Qos Class=Level3 and Target DSCP=CS4. No Qos is defined on Contract and L3Out2. My forward and return traffic when pings originated from Router 1 towards Router 2 are tagged with CS4 properly. But while pinging from Router2 to Router1, forward traffic from Rtr2 to Rtr1 is not tagged with CS4 (checked on ingress interface of Rtr1) but reverse traffic from Rtr1 to Rtr2 is tagged with CS4 (checked on ingress interface of Rtr2). I didn't got the logic behind this.
Can you pls help?

[@Moon-tf4dz]

thanks for your video! it's great. is it different set qos in 'DSCP class-cos translation policy for L3 traffic' ?

[@sandip4983]

we have 3 user defined QoS class, and its common for static EPG and L3Out, from 4.0 release we have 6 user defined QoS class, is this your question ?

[@Moon-tf4dz]

SR yes, if we configure qos for ACI, do we need configure dscp class-cos translation policy for L3traffic in infra tenent and then configure it under Epg or L3out epg as well?

[@sandip4983]

not required to configure on infra tenant

[@Moon-tf4dz]

SR SR ok thanks. Last question that you set cos 5 to EPG2,then why the markdscp to 40 when output ?

[@sandip4983]

@@Moon-tf4dz The default DSCP-to-CoS mapping for CoS 5 is DSCP 40