If you’ve purchased either a UniFi access point or a Haiku/Big A** Fan recently, you may encounter a problem with wall controllers failing to control the associated fan. While the setup nearly works, the final verification step for the wall controller always fails from the app. Further, and confusingly, if you look at the clients list in the Ubiquiti controller, it’s very likely that you’ll see the wall controller listed with a valid IP address. However, that’s not enough to make everything work as expected.
There are two settings that seem to enable the wall controller to work properly. I discovered these after reading an article about setting up a Google Home/Chromecast. You don’t necessarily need to setup a new SSID and VLAN for your wall controller. That’s up to you. However, you will need to enable IGMP Snooping and MulticastDNS for the Wifi that the wall controller and the fan use.
Next, enable multicast DNS: Settings > Services > MDNS > [ON]
As soon as I enabled these, the two wall controllers we have for two Haiku fans began to operate nearly immediately.