Link IoT Edge:Edge application

How do the containers of edge applications communicate with each other?

After you deploy an edge application to a gateway, the edge application uses its application name as the network alias, which is equivalent to the domain name, of its container. Other edge applications can use the application name to access the container of the edge application.

For example, you can create an edge application named mysql8 based on a Docker image of the MySQL 8.0 database and deploy the edge application to a gateway. Then, other edge applications can use mysql8 as the IP address of the MySQL database to access the MySQL database.

How do I enable an edge application running in a container to access the host where the container resides?

When you configure container information for the edge application, set Privilege Mode to Yes or click + Add Device Mapping to add a device mapping.

How do I enable persistent data storage for a container image-based edge application?

When you configure container information for the edge application, click + Add Volume Mapping to add a mapping between a directory in the container and a directory on the host where the container resides. This ensures that no historical data of the edge application will get lost after you upgrade the edge application.

Why are logs of a C program not printed though the program is running properly?

Generally, this issue is caused by the cache mode of the standard output. To fix this issue, we recommend that you add the following code to the beginning of the code of the main function:

if (setvbuf(stdout, NULL, _IOLBF, 0))
   {
       perror("setvbuf failed!") ;
       exit(EXIT_FAILURE);
   }

What are the differences between Function Compute of Alibaba Cloud and that of Link IoT Edge?

• Different modes of code hosting: The code of Function Compute of Alibaba Cloud runs on ECS instances of Alibaba Cloud, while the code of Function Compute of Link IoT Edge runs on the gateway device of Link IoT Edge.
• Different access objects: Function Compute of Alibaba Cloud accesses cloud services through Alibaba Cloud service SDKs built in the runtime environment of functions. Function Compute of Link IoT Edge accesses sub-devices of IoT Platform gateways through specific SDKs built in the runtime environment of functions to obtain sub-device data, and then processes and stores the data.