You are developing an ASP.NET MVC application that will run on Azure.The application uses Event Tracing for Windows (ETW) for logging operations.
You need to retrieve the ETW data for the application from a deployed Azure instance by using the Azure
Diagnostics API.
Which data source should you use?

A.
Azure Diagnostic infrastructure logs

B.
Windows event logs

C.
performance counters

D.
.NET EventSource

Explanation:
Azure Diagnostics 1.2 and 1.3 are Azure extensions that enable you to collect diagnostic telemetry data from a
worker role, web role, or virtual machine running in Azure.
Diagnostics 1.2 and 1.3 enable the collection of ETW and .NET EventSource events.
Example:
EtwProviders>
<EtwEventSourceProviderConfiguration provider=”SampleEventSourceWriter”
scheduledTransferPeriod=”PT5M”>
<Event id=”1″ eventDestination=”EnumsTable”/>
<Event id=”2″ eventDestination=”MessageTable”/>
<Event id=”3″ eventDestination=”SetOtherTable”/>
<Event id=”4″ eventDestination=”HighFreqTable”/>
<DefaultEvents eventDestination=”DefaultTable” />
</EtwEventSourceProviderConfiguration>
</EtwProviders>
Enabling Diagnostics in Azure Cloud Services and Virtual Machines
https://azure.microsoft.com/sv-se/documentation/articles/cloud-services-dotnet-diagnostics/