Flex Connect AP

[hs08]

my WLC located in Datacenter and AP located in branch office. The AP using flex connect so the client will get ip from local switch in branch office. With flex connect scenario is the data interface on WLC will be used, or flex connect only need connect to the WLC management interface only?

[balaji.bandi]

Local Switching: FlexConnect mode allows access points (APs) to switch client data traffic locally rather than tunneling it back to the WLC. This reduces WAN bandwidth usage and minimizes latency for local traffic.

check the flows :

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/213945-understand-flexconnect-on-9800-wireless.html

[hs08]

so any interfaces (except management) is not used, am i right?

[ammahend]

it depends on how you have configured it, even with flexconnect you can setup DHCP traffic to be central.

under policy profile>general>Central DHCP > toggle this button ON or OFF to control this behavior.

[hs08]

the dhcp also configured in local site.

so any interfaces (except management) is not used, am i right?

[Rich R]

> so any interfaces (except management) is not used, am i right?
Short answer - YES.
If you're using local switching and DHCP then there won't be any "data" (client) interface configured on the WLC anyway.

[ammahend]

Correct, other interfaces will not be used, as mentioned the management interface will still be used to deliver other traffic like central authentication, AP registration etc.

[Scott Fella]

The access points still need to communicate with the controller using the management/wireless management.  The controller is the brains for RRM  as an example.  As long as you have the access points as FlexConnect local switching, then user traffic will egress out the switch the access point is connected to. You can find this on the FlexConnect guide if you are using AireOS or the 9800's.

[Scott Fella]

Maybe take a look at this guide, might help you understand what is being sent to the controller vs the swtich.

Locally-switched WLANs map wireless user traffic to discrete VLANs via 802.1Q trunking, either to an adjacent router or switch. If so desired, one or more WLANs can be mapped to the same local 802.1Q VLAN. A branch user, who is associated to a local switched WLAN, has their traffic forwarded by the on-site router. Traffic destined off-site (to the central site) is forwarded as standard IP packets by the branch router. All AP control/management-related traffic is sent to the centralized Wireless LAN Controller (WLC) separately via Control and Provisioning of Wireless Access Points protocol (CAPWAP).

https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/technotes/8-5/cisco-enterprise-mobility-design-guide-8-5.pdf