Viewing Devices

Overview

After a device is created, you can view the device certificate and details, force the device to go offline, and edit device information.

Functions

After a device is created, you can view or operate the device by referring to the following table.

**Table 1** Functions
Function	Description
Viewing a device certificate	A device certificate can be used as a credential for accessing a device. You can click on the right of the Password column to view the device certificate.
Editing a device	Modify information of a created device, except the product name and device ID.
More > Force Offline	Forcibly bring online devices offline. NOTE: This function is applicable only to the online devices that use the MQTT protocol.
More > Deliver Command NOTE: Commands can be delivered only when the protocol type of the product to which the device belongs is MQTT.	LINK can effectively manage devices. The product thing model of a device defines the commands that LINK can deliver to the device. An application can deliver commands to a single device through LINK to remotely control the device. The command delivery configuration is as follows: Select a thing model service that is created in the product to which the device belongs. If no thing model service is available, click Create on the right to create one. Determine whether to enable Synchronous Communication. If this parameter is enabled, a success response is returned after the entire process is complete or a failure response is returned when the timeout period expires. If this parameter is disabled, LINK returns a response immediately after the command is delivered, regardless of the subsequent process. If the device is offline when the command is delivered, a success response is also returned. After the device goes online, LINK forwards the cached command to the device. Select a command under the thing model service of the product. (Optional) Set the delivered command field. This field is displayed based on the field configured in the command. If the field is not configured in the command, it is not displayed. For example, if the delivered field is temperature, a text box is provided to enter the temperature value, such as 37°C. NOTE: An application can also call open northbound APIs of LINK to deliver commands to a single device or a batch of devices.
More > Reset Password	To change the password (that is, device certificate), click Reset Password in the Operation column of the target device.
More > Delete	Delete a created device.

The content on the device details page varies depending on the product protocol type selected during device creation. For details, see Table 2.

**Table 2** Description of the device details page
Protocol Type	Tab Page	Description
MQTT	Basic Information	You can view basic information, including the device ID, online status, and connection address.
	Topics	The system automatically generates default topics, that is, basic topics, based on the product ID and device ID. You can also customize topics as required. Click a device name to access the device details page. Click the Topics tab page and then select Custom Topics. Click Create and configure topic information. Enter a topic name. Select the topic permission. The value can be PUB or SUB. (Optional) Enter a description of the topic. Click OK.
	Device Shadows	A device shadow is used to store the device status reported by devices and the expected status of applications. You can view the information in a list or a JSON file.
ModBus	Basic Information	You can view the basic information, including the device ID, online status, connection address, edge connection configuration, and downloaded EdgeShell.
	Topics	The system automatically generates default topics, that is, basic topics, based on the product ID and device ID. You can also customize topics as required. The procedure is the same as that when MQTT is used.
	Edge Details	You can view the resource status of the host where the device is located, whether the device is online, and the plug-in status.
	Modbus Configuration	Create a Modbus connection point and policy as follows: Click the device name to go to the device details page. Click the Modbus Configuration tab. Click Create Connection Point and configure connection point information. Specify the connection point name in Name. Select the connection point type. TCP/IP and RS232 are supported. Enter the timeout interval of a configuration request, in milliseconds. Enter an IP address of the connection point. Enter an IP port of the connection point. Click OK. After the connection point is created, click the drop-down list button and click Create Policy. Enter a policy name. Enter a value greater than 200 as the collection interval. The maximum polling interval is 86400000 (one day), in the unit of ms. Enter a value ranging from 1 to 125 to as the slave site ID. Enter a value ranging from 0 to 1000000 as the start address. Set the length of the data to be read. The value ranges from 1 to 1000. Enter a function code. Currently, only 01, 02, 03, and 04 are supported. Click Add Point, configure the point mapping, and enter the attribute name of the point to be mapped. For example, if the attribute of collection point 0 is set to temperature, the 0-bit register value (temperature) is reported. This parameter is optional. Click OK. After the policy is created, connect to a device and click Deliver Policy to deliver the policy to the device.
	Plug-in Deployment	Before using this function, you need to install the EdgeShell client and connect it to LINK.
OpcUA	Basic Information	You can view basic information, including the device ID, online status, connection address, and downloaded EdgeShell.
	Topics	The system automatically generates default topics, that is, basic topics, based on the product ID and device ID. You can also customize topics as required. The procedure is the same as that when MQTT is used.
	Edge Details	You can view the resource status of the host where the device is located, whether the device is online, and the plug-in status.
	OPC UA Configuration	Create an OPC UA connection point and policy as follows: Click the device name to access the device details page. Click the OPC UA Configuration tab. Click Create Connection Point and configure connection point information. Specify the connection point name in Name. Enter the TCP connection address, which must start with opc.tcp: and can contain only letters, digits, colons (:), and slashes (/). Example: opc.tcp://127.0.0.1:34561/DataTransferServer Enter a value greater than 200 as the collection interval. The maximum polling interval is 86400000 (one day), in the unit of ms. Determine whether to enable regular collection. If this parameter is set to Yes, the collection start time is a multiple of the collection interval. Set a security policy. Select the security mode. If you select User Authentication, you also need to specify Username and Password. Enter the timeout interval of a request, in the unit of ms. Select a topic for the device to publish messages. Click OK. After the connection point is created, click the drop-down list button and click Create Policy. Enter a policy name. Enter a value greater than 200 as the collection interval. The maximum polling interval is 86400000 (one day), in the unit of ms. Enter a value ranging from 1 to 125 to as the slave site ID. Enter a value ranging from 0 to 1000000 as the start address. Set the length of the data to be read. The value ranges from 1 to 1000. Enter a function code. Currently, only 01, 02, 03, and 04 are supported. Click Add Point, configure the point mapping, and enter the attribute name of the point to be mapped. For example, if the attribute of collection point 0 is set to temperature, the 0-bit register value (temperature) is reported. This parameter is optional. Click OK. After the policy is created, connect to the device and click Deliver Policy to deliver the policy.
	Plug-in Deployment	Before using this function, you need to install the EdgeShell client and connect it to LINK.