Help w/ config: Sonoff Dongle Max on Ubiquiti Unifi LAN to HA on Proxmox. Fails w/ "Error"

Configuration Zigbee
1

Specs:

  1. Unifi UDM Pro 9.5, w/ dedicated IoT 2.4G SSID with “Enhanced IoT connectivity” option checked (“Limits this WiFi Network to 2.4 GHz only with special compatibility settings. Recommended if you are experiencing connectivity issues with 2.4 GHz IoT devices.”)
  2. Sonoff Dongle Max on current firmware, wifi into above ssid. Visible on network AND visible to HA instance (auto discovered).
  3. HA running on homelab server wired into network: proxmox with HA in its own lxc container (docker in another).

Trying to set up dongle. In HA both on mobile and on PC, dongle is discovered under integrations. I click Add, choose either automatic or advanced, it spins a bit (Loading next step for Zigbee Home Automation), then I get a simple “Error” dialogue with only OK to back out.

This happens when I connect the dongle via ethernet also, btw.

Recommendations? TIA!

2

Uncertain if you have this already, if not - put the coordinator in the same vlan as HA.

3

Ensure that the EFR32MG24 mode of the Dongle-M is in Zigbee coordinator mode. If you are unsure, you can manually switch to Thread RCP mode and then switch to Zigbee coordinator mode.