MQTT fails: "identifier rejected" after broker update to 6.2.0

Configuration
1

I am using umqtt.simple2 in Micropython on ESP8266.
I literally installed this for the first time last night and it was working fine. This morning, updated MQTT broker to 6.2.0 (with no changes on client) and now fails to connect:

from umqttsimple2 import MQTTClient
client_id = b'd1234567' 
mqtt_server = '192.168.9.9'
client = MQTTClient(client_id, mqtt_server, user='***', password='***')
client.connect()

throws error 22 (“identifier rejected”)

Has anyone else had similar issues, or suggest where to begin troubleshooting this?

regards,
Nick

2

solved: client is created with keepalive=0 as its default
setting:
client = MQTTClient(client_id, mqtt_server, user='***', password='***', keepalive=60)
fixed it

2 Likes
3

After updating to 6.2.0, some MQTT devices, in particular MegaD - 2561, stopped working. I rolled back to version 6.1.3 for now.