Azure Web Application Restarting : Root Cause?

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Hi!
I continue sharing experiences when working with Microsoft Developers tools, different scenarios you may face each day :)

One of the scenarios we found, was an Azure Web Application restarting and wanted to identify the reason or Route Cause, so we can articulate some action plan to mitigate this, in order of ensuring the Customers have the best experience ever when using the Azure Web Application.
But first, some considerations about instances itself

Regarding Scaling number of instances
The starting point once an Azure Web Application is created, is 1 instance. Now, once the application begins to grow in functionality, you can add more resources, or instances, to handle the needs for your business > this process is known as "Scaling out": by this, you can add more instances so you ensure your application takes benefit of most of the power that we can offer within Azure. In fact, the Scaling up process runs for several resources offered by Microsoft in Azure.

But you need to get attached to just 1 instance? Well, that's the Magic about Azure : you can add more instances, and this process is very simple, and that was the solution applied on the Scenario stated.

Speaking with property, we can define 2 processes for what we know as "Scale" that is basically a workflow:

Scale up:
You can get more resources such as CPU, memory, disk space, and extra features such as dedicated VMs, custom domains and certificates, staging slots, autoscaling, and more. The Scale up process is applied just by changing the Pricing tier of the App Service plan you are running.
Scale out:
Increase the number of VM instances that run your app. The maximum value to scale out varies from 20 instances to 50 in Premium tier, take in consideration that it will depend on your pricing tier.

Note: The scale settings take only seconds to apply and affect all apps in your App Service plan. They do not require you to change your code or redeploy your application.

Please take a look a the wordings on the following documentation :
Scale instance count manually or automatically how to use autoscaling, to scale instance count automatically based on predefined rules and schedules.

For further details about configuring Autoscale, please check:
Scale an app in Azure App Service
Scaling apps in an App Service Environment

Enjoy!

Rosana