Overview

This instrumentation method uses Azure’s Sidecar pattern to monitor containerized Linux Azure App Service workloads.

Prerequisites

• Your Azure App Service application is containerized
• You are using a programming language supported by a Datadog tracing library
• You have a Datadog API key

Instrument your application

1. Integrate the Datadog tracer into your containerized application
2. Create your Linux Web App
3. Add Datadog environment variables as application settings
4. Add the Datadog sidecar

Integrate the Datadog tracer

1. Add the following lines to the Dockerfile for your main application:

   • .NET

   RUN mkdir -p /datadog/tracer
   RUN mkdir -p /home/LogFiles/dotnet
   
   ADD https://github.com/DataDog/dd-trace-dotnet/releases/download/v2.51.0/datadog-dotnet-apm-2.49.0.tar.gz /datadog/tracer
   RUN cd /datadog/tracer && tar -zxf datadog-dotnet-apm-2.49.0.tar.gz
   

   This installs and configures the Datadog tracer within your application container.

2. Build the image and push it to your preferred container registry.

Full example Dockerfile

# Stage 1: Build the application
FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
WORKDIR /app

# Copy the project file and restore dependencies
COPY *.csproj ./
RUN dotnet restore

# Copy the remaining source code
COPY . .

# Build the application
RUN dotnet publish -c Release -o out

# Stage 2: Create a runtime image
FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS runtime
WORKDIR /app

# Copy the build output from stage 1
COPY --from=build /app/out ./

# Datadog specific
RUN mkdir -p /datadog/tracer
RUN mkdir -p /home/LogFiles/dotnet

ADD https://github.com/DataDog/dd-trace-dotnet/releases/download/v2.49.0/datadog-dotnet-apm-2.49.0.tar.gz /datadog/tracer
RUN cd /datadog/tracer && tar -zxf datadog-dotnet-apm-2.49.0.tar.gz

# Set the entry point for the application
ENTRYPOINT ["dotnet", "<your dotnet app>.dll"]

Create your Linux Web App

1. In the Azure Portal, go to App Services and select Create.
2. On the Basics tab, provide the required details.
   • For Publish, select Container.
   • For Operating System, select Linux. Then, select Next: Container >.
3. On the Container tab, provide the required details.
   • For Sidecar support, select Enabled.
   • For Image Source, select your chosen registry.
   • Specify the Registry, Image, Tag, and Port for your container image.
4. Select Review + create, then select Create.

Add Datadog environment variables

1. In the Azure portal, select your app.

2. In the left menu, select Configuration > Application settings.

3. Add the following environment variables as application settings.

   DD_API_KEY (Required)

   Your Datadog API key.
   Alternatively, you can source your API key (and other sensitive information) from Azure Key Vault. See Use Key Vault references as app settings in Azure App Service.

   DD_SITE

   datadoghq.com
   Corresponds to your Datadog site. Defaults to datadoghq.com.

   DD_SERVICE

   Supply a service name to be displayed in your Datadog Software Catalog. See Unified Service Tagging.

   DD_ENV

   A name for your environment, such as staging or prod. See Unified Service Tagging.

   DD_SERVERLESS_LOG_PATH

   /home/Logfile/*.log
   Corresponds to the path where you write your application logs. If you have changed this location, specify your custom location in this setting.

   DD_DOTNET_TRACER_HOME (Required)

   /datadog/tracer

   DD_TRACE_LOG_DIRECTORY (Required)

   /home/Logfiles/dotnet

   CORECLR_ENABLE_PROFILING (Required)

   1

   CORECLR_PROFILER (Required)

   {846F5F1C-F9AE-4B07-969E-05C26BC060D8}

   CORECLR_PROFILER_PATH (Required)

   /datadog/tracer/Datadog.Trace.ClrProfiler.Native.so

Add the Datadog sidecar

1. In the Azure portal, select your app.
2. In the left menu, select Deployment Center.
3. Select Add. Under Add container, provide the following details:
   • Name: datadog
   • Image source: Docker Hub or another registry
   • Image type: Public
   • Registry server URL: sitecontainerssampleacr.azurecr.io
   • Image and tag: datadog-dotnet:2.0
   • Port: 8126
4. Select Apply.

Next steps

After you finish instrumenting your application, go to the Serverless > Azure page in Datadog to see your observability data. Your application logs are available in Log Explorer, and your traces are available in Trace Explorer.