What exactly does a 'service ... start' instruction mean for a .NET Core application?

Question

I need to deploy a .NET Core app (that uses an MVC pattern) that's already been configured to run on an Ubuntu VM that's running under Azure. NGINX appears to be in use as a reverse proxy server. I have a set of instructions for deployment, where the final step is to run this instruction on an Ubuntu terminal:

service myservicename start

What exactly is this instruction doing and where is it documented? Is it part of the .NET CLI, or something to do with NGINX or Linux? And can I derive anything from the use of this instruction as to what form the application is running in? For example does it infer that the app is running as some type of Linux service?

Answer 1

I figured out that the .NET app is running under the Linux systemd "System and Service Manager", and the command is to start the app under that service manager.

If I run systemctl status myservicename it shows me a description of the service, and its main details, including the location of the user-created service file for the app. The service can then be examined using the following from a Linux terminal:

cat [serviceFileLocation]

(eg serviceFileLocation might be /etc/systemd/system/myservicename.service )

The content of the service file then reveals that the main service command ExecStart is configured to run the application .dll via the dotnet core runtime:

Here's a useful startup guide for .NET Core running under systemd