Applying QOS - centalized or localized policy ?

[carl_townshend]

Hi guys

im struggling to know when you use localised vs centralized policies.

can you apply a qos policy with a centralised data policy ? Or do these need to be localised policies ?

in what instances do you need to use either ?

[Joseph W. Doherty]

What kind of network environment and what would be applying the QoS policies?

As aside, in general, it's nice to have one QoS policy, but sometimes unique parts of a network need a unique QoS policy.

[carl_townshend]

Full mesh, dual isr 4k on each site, looking to give voice and video qos, could I just write a centralized data policy for this ?

[Joseph W. Doherty]

Sorry, I don't understand your topology (full mesh? using ISRs) and what you understand a centralized data policy is vs. a localized data policy.  Hopefully, someone else will better understand your question or you'll need to provide further details.

[Kanan Huseynli]

Hi,

you need localized policy to define QoS scheduler and to create re-write policy (this part is optional). Also, you need to use QoS-Map/ Re-write policy to interface (of course, localized policy should be attached to device with device template).

But to have actual action you need to map traffic to qos-map class. This part can be done by localized policy using sdwan access-list (match and set) OR you can do via centralized policy by match and set forwarding class (FC).

You can follow this workflow from config guide (it uses centralized policy to match ans set FC):

https://www.cisco.com/c/en/us/td/docs/routers/sdwan/configuration/qos/ios-xe-17/qos-book-xe/forwarding-qos.html#Cisco_Concept.dita_aa3e0d07-462e-463f-8f45-681f38f61ab0

[Joseph W. Doherty]

Ah, didn't realize @carl_townshend was asking in reference to SDWAN.