Failed to connect: Not authorized. loop_forever() will retry connection

[kkakji]

Prerequisites

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• Read the readme (especially the
  "Known limitations" section) and look at the examples.
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  to test your assumptions.

Question

(1) make account file
cd /etc/mosquitto
mosquitto_passwd -c .account userid
Password: passwd
Reenter password: passwd

(2) /etc/mosquitto/mosquitto.conf
.....
password_file /etc/mosquitto/.account
.....

(3) source code
import time
import paho.mqtt.client as mqtt

MQTT_SERVER = "127.0.0.1"
MQTT_PORT = 1883
MQTT_TOPIC = "wind"

def on_connect(client, userdata, flags, reason_code, properties):
if reason_code.is_failure:
print(f"Failed to connect: {reason_code}. loop_forever() will retry connection")
else:
# we should always subscribe from on_connect callback to be sure
# our subscribed is persisted across reconnections.
#client.subscribe("$SYS/#")
client.subscribe(MQTT_TOPIC)

.......

client_userdata = 1

mqttc = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)

......
mqttc.on_connect = on_connect
......

username = "userid"
password = "passwd"

mqttc.username_pw_set(username, password)
mqttc.user_data_set([])
mqttc.connect(MQTT_SERVER, MQTT_PORT)

.....
mqttc.loop_forever()

Result

Failed to connect: Not authorized. loop_forever() will retry connection

Environment

It's often helpful for us to know how you are using the library so please provide:

• Python version:
• Library version:
• Operating system (including version):
• MQTT server (name, version, configuration, hosting details):