Numerous users of the smarthome server software Home Assistant experienced a surprise: devices communicating with the server via MQTT could no longer transmit data or be controlled from the server. ESP in-house components in particular, but also ZigBee devices, were affected.
This is due to an update to Home Assistant’s MQTT broker. This add-on enables communication between devices using the MQTT protocol. With the new version 6.0.1 However, the automatic detection (discovery) of these devices no longer works as before.
You should not accept this update offer for now.
Therefore, such components no longer appear in the Home Assistant system and can no longer be controlled. On the Github page of the add-on, corresponding messages pile up.
Problem case MQTT broker 6.0.1
The only workaround at the moment is to go back to the previous version. You can reach the restore function in the Supervisor-menu under Backup. Double click on the old version 5.1.1 and then select restore.
The version 5.1.1 should be restored to be able to control all MQTT components again.
After a reboot the MQTT components should work again.