Cisco WLC & AP Uplinks

[Evlaa2021]

Going back to basics here what is the recomendation for uplinks / trunk connections to Cisco WLC in terms of spanning-tree

Our WLCs are setup to use LAG and we're trunking multiple VLANs across the trunk to the WLC so i would imagine spanning-tree should be enabled?

For Cisco APs we have spanning-tree port-fast enabled as we are central switching and not doing any flex connect?

Just needing to sanity check due to strange issues happening on our network.

[marce1000]

  - If you are not doing flexconnect and or capwap only , then you can just use 'host mode' for the access point port-connection, the VLANS/Wlans are terminated on the controller and the necessary traffic is then tunneled to the ap with capwap-protocol only.

 M.

[ammahend]

Yes, your config sounds correct, switch ports connecting to WLC should be trunk, allowing VLANs needed for your SSID operation, and native VLAN set to management vlan of WLC.

when you enable LAG both interface forward traffic, its not like spanning tree will block one link, if that is what you are asking.

Cisco APs we have spanning-tree port-fast enabled, this sounds good too, it just means when a port flaps switch wont have to wait 50+ seconds to bring the port up and can do much faster.  since you are centally switch these ports can be access port, as mentioned below, all traffic will be tunneled to WLC over CAPWAP.

[Rasika Nayanajith]

WLCs are not running spanning tree protocol. In that way you can leave your normal switch configuration without worrying about will WLC cause STP loops. Below gives a sample configuration

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-vlan/68100-wlan-controllers-vlans.html 

If you want, you can enable "portfast" on that trunk port connecting WLC.

HTH
Rasika
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[Leo Laohoo]

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@Evlaa2021 wrote:

Our WLCs are setup to use LAG and we're trunking multiple VLANs across the trunk to the WLC so i would imagine spanning-tree should be enabled?

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IF the WLC uplink ports are in a LAG then STP is disabled.  

That is the function of LAG:  It binds/bundles multiple physical links into a single logical link.  How is "STP" going to work on a single logical link?  STP can't.