Application Insights for Azure VMs and virtual machine scale sets

This article explains how to enable Application Insights monitoring through autoinstrumentation for IIS-hosted ASP.NET and ASP.NET Core applications on Azure Virtual Machines and Azure Virtual Machine Scale Sets. It covers how to deploy the Application Insights Agent using a virtual machine extension, which autocollects the same dependency signals as the SDK, and provides guidance for automating large-scale deployments with PowerShell.

Note

• For Java applications, use the Application Insights Java 3.0 agent, which autocollects the most popular libraries, frameworks, logs, and dependencies, along with many other configurations.

• Node.js and Python applications running on Azure VMs and Azure Virtual Machine Scale Sets don't support autoinstrumentation. Use the Azure Monitor OpenTelemetry Distro instead.

For a complete list of supported autoinstrumentation scenarios, see Supported environments, languages, and resource providers.

Prerequisites

Before you install the Application Insights Agent extension, you need a connection string. Create a new Application Insights resource or copy the connection string from an existing one.

Enable monitoring for virtual machines

You can use the Azure portal or PowerShell to enable monitoring for VMs.

Azure portal

1. In the Azure portal, go to your Application Insights resource. Copy your connection string to the clipboard.

   

2. Go to your virtual machine. Under the Settings section in the menu on the left side, select Extensions + applications > Add.

   

3. Select Application Insights Agent > Next.

   

4. Paste the connection string you copied in step 1 and select Review + create.

   

PowerShell

Note

New to PowerShell? Check out the Get started guide.

Install or update the Application Insights Agent as an extension for Azure virtual machines:

# define variables to match your environment before running
$ResourceGroup = "<myVmResourceGroup>"
$VMName = "<myVmName>"
$Location = "<myVmLocation>"
$ConnectionString = "<myAppInsightsResourceConnectionString>"

$publicCfgJsonString = @"
{
    "redfieldConfiguration": {
        "instrumentationKeyMap": {
        "filters": [
            {
            "appFilter": ".*",
            "machineFilter": ".*",
            "virtualPathFilter": ".*",
            "instrumentationSettings" : {
                "connectionString": "$ConnectionString"
            }
            }
        ]
        }
    }
    }
"@

$privateCfgJsonString = '{}'
	
Set-AzVMExtension -ResourceGroupName $ResourceGroup -VMName $VMName -Location $Location -Name "ApplicationMonitoringWindows" -Publisher "Microsoft.Azure.Diagnostics" -Type "ApplicationMonitoringWindows" -Version "2.8" -SettingString $publicCfgJsonString -ProtectedSettingString $privateCfgJsonString

Note

For more complicated at-scale deployments, you can use a PowerShell loop to install or update the Application Insights Agent extension across multiple VMs.

Query the Application Insights Agent extension status for Azure virtual machines:

Get-AzVMExtension -ResourceGroupName "<myVmResourceGroup>" -VMName "<myVmName>" -Name ApplicationMonitoringWindows -Status

Get a list of installed extensions for Azure virtual machines:

Get-AzResource -ResourceId "/subscriptions/<mySubscriptionId>/resourceGroups/<myVmResourceGroup>/providers/Microsoft.Compute/virtualMachines/<myVmName>/extensions"

Uninstall the Application Insights Agent extension from Azure virtual machines:

Remove-AzVMExtension -ResourceGroupName "<myVmResourceGroup>" -VMName "<myVmName>" -Name "ApplicationMonitoring"

Note

Verify installation by selecting Live Metrics Stream within the Application Insights resource associated with the connection string you used to deploy the Application Insights Agent extension. If you're sending data from multiple virtual machines, select the target Azure virtual machines under Server Name. It might take up to a minute for data to begin flowing.

Enable monitoring for virtual machine scale sets

You can use the Azure portal or PowerShell to enable monitoring for virtual machine scale sets.

Azure portal

Follow the prior steps for VMs, but go to your virtual machine scale sets instead of your VM.

PowerShell

Install or update Application Insights Agent as an extension for virtual machine scale sets:

# Set resource group, vmss name, and connection string to reflect your environment
$ResourceGroup = "<myVmResourceGroup>"
$VMSSName = "<myVmName>"
$ConnectionString = "<myAppInsightsResourceConnectionString>"
$publicCfgHashtable =
@{
  "redfieldConfiguration"= @{
    "instrumentationKeyMap"= @{
      "filters"= @(
        @{
          "appFilter"= ".*";
          "machineFilter"= ".*";
          "virtualPathFilter"= ".*";
          "instrumentationSettings" = @{
            "connectionString"= "$ConnectionString"
          }
        }
      )
    }
  }
};
$privateCfgHashtable = @{};
$vmss = Get-AzVmss -ResourceGroupName $ResourceGroup -VMScaleSetName $VMSSName
Add-AzVmssExtension -VirtualMachineScaleSet $vmss -Name "ApplicationMonitoringWindows" -Publisher "Microsoft.Azure.Diagnostics" -Type "ApplicationMonitoringWindows" -TypeHandlerVersion "2.8" -Setting $publicCfgHashtable -ProtectedSetting $privateCfgHashtable
Update-AzVmss -ResourceGroupName $vmss.ResourceGroupName -Name $vmss
# Note: Depending on your update policy, you might need to run Update-AzVmssInstance for each instance

Get a list of installed extensions for virtual machine scale sets:

Get-AzResource -ResourceId "/subscriptions/<mySubscriptionId>/resourceGroups/<myResourceGroup>/providers/Microsoft.Compute/virtualMachineScaleSets/<myVmssName>/extensions"

Uninstall the application monitoring extension from virtual machine scale sets:

# set resource group and vmss name to reflect your environment
$vmss = Get-AzVmss -ResourceGroupName "<myResourceGroup>" -VMScaleSetName "<myVmssName>"
Remove-AzVmssExtension -VirtualMachineScaleSet $vmss -Name "ApplicationMonitoringWindows"
Update-AzVmss -ResourceGroupName $vmss.ResourceGroupName -Name $vmss.Name -VirtualMachineScaleSet $vmss
# Note: Depending on your update policy, you might need to run Update-AzVmssInstance for each instance

Frequently asked questions

How can I disable client-side monitoring for ASP.NET Core apps?

Client-side monitoring is enabled by default for ASP.NET Core apps. If you want to disable it, define an environment variable in the server with the following information:

• Name: APPINSIGHTS_JAVASCRIPT_ENABLED
• Value: false

Troubleshooting

Find troubleshooting tips for the Application Insights Monitoring Agent extension for .NET applications running on Azure virtual machines and virtual machine scale sets.

If you're having trouble deploying the extension, review the execution output that's logged to files found in the following directories:

C:\WindowsAzure\Logs\Plugins\Microsoft.Azure.Diagnostics.ApplicationMonitoringWindows\<version>\

If your extension deployed successfully but you're unable to see telemetry, it could be one of the following issues covered in Agent troubleshooting:

• Conflicting DLLs in an app's bin directory
• Conflict with IIS shared configuration

Test connectivity between your application host and the ingestion service

Application Insights SDKs and agents send telemetry to get ingested as REST calls to our ingestion endpoints. You can test connectivity from your web server or application host machine to the ingestion service endpoints by using raw REST clients from PowerShell or curl commands. See Troubleshoot missing application telemetry in Azure Monitor Application Insights.

Release notes

2.8.44

• Updated Application Insights .NET/.NET Core SDK to 2.20.1 - red field.
• Enabled SQL query collection.
• Enabled support for Microsoft Entra authentication.

2.8.42

Updated Application Insights .NET/.NET Core SDK to 2.18.1 - red field.

2.8.41

Added the ASP.NET Core autoinstrumentation feature.

Next steps

• Deploy your application on Virtual Machine Scale Sets.
• Application Insights availability tests