AP Capwap Multicast: unicast

[absuizo14]

Greetings,

Is changing the AP Capwap Multicast mode from multicast to unicast cause a downtime to a 8900-80 wlc running 17.3.5a. i need to change it to unicast for mDNS bridging since the ip address of the access points are on a different vlan from the wlc's wireless management interface.

[Rasika Nayanajith · Accepted solution]

Below is from the 9800 best practice config guide given below. Unicast mode is not recommended if you got a large scale AP network. By looking at that even it may not supported on your 9800-80 controller.
https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9800-series-wireless-controllers/guide-c07-743627.html#Multicastforwardingmode 

"Multicast-forwarding mode is the recommended setting. Use unicast forwarding only for small deployments and when multicast routing support in the network infrastructure is not possible. Unicast forwarding is not supported on the C9800-80, C9800-40, and C9800-CL medium and large template platforms."

In your scenario, recommended way is to enable multicast on your AP management vlan & WLC management vlan.

HTH
Rasika
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