Azure App Service on Linux has several prefabricated Docker images that support applications written in languages such as .NET core, PHP, and Node.js. App Service also supports using your own Docker image to spin up a container for your application. A useful configuration feature of App Service on Linux is the Startup File configuration that you can set as part of configuring the runtime stack. The value that you specify for the configuration overrides the
CMD instruction of the Dockerfile that creates the runtime of the application. If you are not aware of this configuration option, we will soon deploy an application that uses this configuration option soon, so keep reading.
The Docker documentation states that if your Dockerfile has both
ENTRYPOINT instructions, then
CMD arguments are appended to the end of the command generated by the
ENTRYPOINT instruction. A necessary condition for this feature to work is that you must use the
exec form of the
ENTRYPOINT instruction in your Dockerfile. In simple terms, assume that your Dockerfile has the following instructions.