Hello MS Techie,
to test if an application is still working can be done in two ways.
The application can actively send heartbeats, messages, to some reliable mechanism that will alert you if no messages arrive anymore.
The other way is by asking about the current status of an application. If the answer is wrong or there is no answer, an alert can be generated.
You do not want to make use of Log Analytics?
For the first step, you probably need to either build something yourself.
Regarding the other step, Application Insights has this availability test (for Rest endpoints):
Unfortunately, Log Analytics is needed for Application Insights.
I wonder why Log Analytics is not applicable. Yes, there are costs involved but non-available services due to errors could cost much more.
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