问题
I am using python mosquitto(paho) library. I got the problem of Unexpected disconnection. I found constantly dropping and connection with the server. . I am unable to find the problem. some times it shows [Error 104] connection reset by peer. I hosted my broker on amazon web services...
my error is ---
Connected to xx.xx.xx.xx:1883
Unexpected disconnection.
Connected to xx.xx.xx.xx:1883
Unexpected disconnection.
Connected to xx.xx.xx.xx:1883
I am passing QOS=2, retain = true, clean session =false, no username and password, lwt =none , port= 1883, ip = server hosted on aws, client id = publisher
My code includes---
import time
import paho.mqtt.client as mqtt
class MqttCommunication(object):
def __init__(self):
self.current_module = "Mqtt Communication class"
self.clientID = clientId
self.name = thread_name
self.DEBUG = True
self.MQTT_HOST = ""
self.MQTT_PORT = 1883
self.MQTT_USERNAME = ""
self.MQTT_PASSWORD = ""
self.MQTT_CLIENT_ID = self.clientID
self.MQTT_TOPIC = ""
self.MQTT_QOS = 0
self.MQTT_RETAIN = None
self.MQTT_CLEAN_SESSION = None
self.MQTT_LWT = ""
self.client = mqtt.Client(self.MQTT_CLIENT_ID, clean_session=self.MQTT_CLEAN_SESSION)
self.on_connect = None
self.on_disconnect = None
self.on_message = None
self.on_subscribe = None
self.on_unsubscribe = None
self.on_publish = None
self.client.on_connect = self.mqtt_on_connect
#self.client.on_message = self.mqtt_on_message
self.client.on_disconnect = self.mqtt_on_disconnect
self.client.on_subscribe = self.mqtt_on_subscribe
self.client.on_unsubscribe = self.mqtt_on_unsubscribe
self.client.on_publish = self.mqtt_on_publish
def connectHost(self,mqtt_host,mqtt_port,mqtt_username,mqtt_password):
self.MQTT_USERNAME = mqtt_username
self.MQTT_PASSWORD = mqtt_password
self.MQTT_HOST = mqtt_host
self.MQTT_PORT = mqtt_port
try:
self.client.username_pw_set(self.MQTT_USERNAME, self.MQTT_PASSWORD)
print self.client.connect(self.MQTT_HOST,self.MQTT_PORT,60)
print self.MQTT_HOST
except Exception, e:
print "Error connecting to %s:%d: %s" % (mqtt_host, mqtt_port, str(e))
return True
def disconnectHost(self):
self.client.disconnect()
return True
def mqttSettings(self,qos,mqtt_retain,mqtt_clean_session,mqtt_lwt):
self.MQTT_QOS = qos
self.MQTT_RETAIN = mqtt_retain
self.MQTT_CLEAN_SESSION = mqtt_clean_session
self.MQTT_LWT = mqtt_lwt
return True
def subscribeTopic(self,topic):
self.MQTT_TOPIC = topic
self.client.subscribe(self.MQTT_TOPIC, qos=self.MQTT_QOS)
return True
def unsubscribeTopic(self,topic):
self.client.unsubscribe(self.MQTT_TOPIC)
return True
def setClientId(self,clientID):
self.MQTT_CLIENT_ID= clientID
return True
def getClientId(self):
return self.MQTT_CLIENT_ID
def publishData(self,topic,message,qos):
self.client.publish(topic,message,qos)
return True
# The callback for when the client receives a CONNACK response from the server.
def mqtt_on_connect(self,client, userdata, flags, rc):
if rc == 0:
print "Connected to %s:%s" % (self.MQTT_HOST, self.MQTT_PORT)
time.sleep(3)
elif rc == 1:
print "Connection refused - unacceptable protocol version"
elif rc == 2:
print "Connection refused - identifier rejected"
elif rc == 3:
print "Connection refused - server unavailable"
elif rc == 4:
print "Connection refused - bad user name or password"
elif rc == 5:
print "Connection refused - not authorised"
else:
print "Connection failed - result code %d" % (rc)
# The callback for when a PUBLISH message is received from the server.
def mqtt_on_message(self , client, userdata, msg):
#print msg
print(msg.topic+" : "+str(msg.payload))
def mqtt_on_disconnect(self, client, userdata, rc):
if rc != 0:
print("Unexpected disconnection.")
else:
print('hello from disconnect')
def mqtt_on_publish(self, client, userdata, mid):
"""
What to do when a message is published
"""
#print "publish"
def mqtt_on_subscribe(self,client, userdata, mid, granted_qos):
"""
What to do in the event of subscribing to a topic"
"""
#logging.debug("Subscribe with mid " + str(mid) + " received.")
def mqtt_on_unsubscribe(self, client, userdata, mid):
"""
What to do in the event of unsubscribing from a topic
"""
#logging.debug("Unsubscribe with mid " + str(mid) + " received.")
sharing some logs from log file....
1483168399: Client publisher already connected, closing old connection.
1483168399: Client publisher disconnected.
1483168399: New client connected from xx.xx.xx.xx as publisher (c0, k60).
1483168401: New connection from xx.xx.xx.xx on port 1883.
1483168401: Client publisher already connected, closing old connection.
1483168401: Client publisher disconnected.
1483168401: New client connected from xx.xx.xx.xx as publisher (c0, k60).
1483168404: New connection from xx.xx.xx.xx on port 1883.
1483168404: Client publisher already connected, closing old connection.
1483168404: Client publisher disconnected.
1483168404: New client connected from xx.xx.xx.xx as publisher (c0, k60).
1483168405: New connection from xx.xx.xx.xx on port 1883.
1483168405: Client publisher already connected, closing old connection.
1483168405: Client publisher disconnected.
1483168405: New client connected from xx.xx.xx.xx as publisher (c0, k60).
1483168408: New connection from xx.xx.xx.xx on port 1883.
1483168408: Client publisher already connected, closing old connection.
1483168408: Client publisher disconnected.
1483168408: New client connected from xx.xx.xx.xx as publisher (c0, k60).
1483168410: New connection from 27
回答1:
You have multiple connections using the same client_id. client_id's have to be unique, the broker will only allow one connection with a client_id at a time and will kick the oldest one off the broker when a new connection is formed. If you have reconnection logic in place then the old client will try and reconnect which will kick the new client off, this ends up in a feed back look with no client managing to stay connected to the broker.
It looks like you have hard coded your client_id to "publisher" from the logs, this needs to be changed to be a unique value, normally I would set a to a prefix like "pub_" then add on a random number, a timestamp or some other identifier (e.g. thead number/name)
来源：https://stackoverflow.com/questions/41366328/mosquitto-unexpected-disconnection