you can view logs on the device or in IoT Platform.
Prerequisites
For more information, see Example.
Device logs
You can view the running result on the device.-
Logs about device connection
The following log data indicates that the device is connected to IoT Platform.[1583135792.733][LK-0313] MQTT user calls aiot_mqtt_connect api, connect [1583135792.733][LK-0317] LightSwitch&a18wP****** [1583135792.733][LK-0318] 3FC4A3DED5AC5F31C4969CBB1868758B17FAB2E5070FC51C9880910472****** [1583135792.733][LK-0319] a18wP******.LightSwitch|timestamp=2524608000000,_ss=1,_v=sdk-c-4.0.0,securemode=2,signmethod=hmacsha256,ext=1,| establish mbedtls connection with server(host='a18wP******.iot-as-mqtt.cn-shanghai.aliyuncs.com', port=[443]) success to establish mbedtls connection, fd = 6(cost 44763 bytes in total, max used 47675 bytes) [1583135792.888][LK-0313] MQTT connect success in 147 ms AIOT_MQTTEVT_CONNECT
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Logs about topic subscription
If you want to send a broadcast message to all devices under a product, the devices must subscribe to the broadcast topic, such as
/broadcast/a18wP******/test
. After subscription, the following log data is generated:[1624933980.266][LK-0309] sub: /broadcast/a18wP******/test suback, res: -0x0000, packet id: 1, max qos: 1
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Logs about message broadcasting
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Send a broadcast message to a specified topic
You can call the PubBroadcast operation of IoT Platform to send a broadcast message to a specified topic. The following log data indicates that thehelloworld
message is sent to the/broadcast/a18wP******/test
topic:[1624934078.899][LK-0309] pub: /broadcast/a18wP******/test [LK-030A] < 68 65 6C 6C 6F 77 6F 72 6C 64 | helloworld pub, qos: 0, topic: /broadcast/a18wP******/test pub, payload: helloworld
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Send a broadcast message to all online devices
You can also call the PubBroadcast operation of IoT Platform to send a broadcast message such ashelloworld
to all online devices under a specified product. In this example, the following log data is generated.- Log data:
[1624934109.099][LK-0309] pub: /sys/a18wP******/LightSwitch/broadcast/request/1409701944049****** [LK-030A] < 68 65 6C 6C 6F 77 6F 72 6C 64 | helloworld pub, qos: 1, topic: /sys/a18wP******/LightSwitch/broadcast/request/1409701944049****** pub, payload: helloworld
- Log description:
/sys/a18wP******/LightSwitch/broadcast/request/1409701944049******
indicates the topic to which the broadcast message is sent.1213074107617******
indicates the message ID. For more information, see Broadcast messages.
- Log data:
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IoT Platform logs
You can log on to the IoT Platform console . In the left-side navigation pane, choose Select a product and then view the communication logs of the device. . Select a product to
What to do next
For more information about error messages in logs, see Common error codes