My home network runs exclusively on Ubiquiti UniFi hardware which is fantastic, but it hides the WMM configuration setting from the web-based UI. Disabling Airtime Fairness and WMM is one of the first things you should do for any SSID dedicated to low-powered IoT devices like LIFX smart bulbs.

Prequisites

  1. Upgrade to the latest stable UniFi firmware
  2. Enable Advanced Features in the UniFi Network Controller
  3. Add SSH Keys to your UniFi Devices.

Procedure

This procedure will disable WMM on the IoT network only and leave it enabled on all other SSIDs.

  1. Connect via SSH to the UAP and run the following command:

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    $ fgrep IoT /tmp/running.cfg
    aaa.1.ssid=IoT
    wireless.1.ssid=IoT
    

    Make a note of the value of the line that begins with the word wireless. In this example, it’s 1.

  2. Connect via SSH to your UniFi Controller and create a config.properties file in the correct site folder

  3. Add config.system_cfg.1=wireless.1.wmm=disabled to the config.properties file. This will disable WMM on the IoT SSID (identified by wireless.1) on all APs.

  4. Force provision all UAPs so they pick up the site-wide configuration.

  5. Connect via SSH and check the configuration has been applied:

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    $ fgrep wmm /tmp/running.cfg
    wireless.1.wmm=enabled
    wireless.2.wmm=enabled
    wireless.3.wmm=enabled
    wireless.4.wmm=enabled
    wireless.5.wmm=enabled
    wireless.1.wmm=disabled
    

    You’ll see that UniFi enables WMM by default across all SSIDs but the last line disables it specifically for the wireless.1 SSID.