Azure Application Gateway: Private Endpoint Custom Name Solution Reference Architecture and Tests

Goals

• Provide an enviroment to test Application Gateway features and test custom name solution for Azure services.

Architecture

Tests

Azure Application Gateway

All backend pools are configured with the service FQDN.

Application Gateway Implicit Tests

If Terraform deployment is successful, then the following features are working:

Service	Feature
Azure Key Vault	Reference a certificate in a Private Endpoint Protected Key Vault.
Application Gateway	No Public IP.
Application Gateway	Subnet: No need to define specific inbound rules in NSGs.
Application Gateway	Subnet: route 0.0.0.0 traffic to a Firewall.

Application Gateway Explicit Tests

Test developed using .NET 6.0.

Service	Enabled	Protocol	Result	Test Description	Notes
Cosmos DB SQL API	[x]	https	Pass	Create a database	Uses endpoint & key. Requires the client to disable endpoint rediscovery.
Storage Account (Blob)	[x]	https	Pass	Create a container	Uses DefaultAzureCredential (AAD).
Key Vault	[x]	https	Pass	Read a secret	Uses DefaultAzureCredential (AAD).
Azure Functions	[x]	https	Pass	Returns a 200 response
Azure Functions KUDU	[ ]	https		TODO
Event Hubs AmqpWebSockets	[x]	https	Pass	Send messages	Uses DefaultAzureCredential (AAD).
Event Hubs AmqpTcp	[x]	tls	Pass	Send messages	Uses DefaultAzureCredential (AAD).
PostegreSQL Single Server User Password	[x]	tcp	Pass	Open connection
PostegreSQL Single Server AAD	[ ]	tcp	Pass	Open connection	Uses DefaultAzureCredential (AAD) and TrustServerCertificate=true or SSL Mode=VerifyCA.
SQL Server User Password	[x]	tcp	Pass	Open connection	Uses TrustServerCertificate=true.
SQL Server AAD	[ ]	tcp	Fail	Open connection	If a token is used to authenticate then the User ID with the server name cannot be set in the connection string. Attempting to use the token as password also fails.

The following features are also tested:

Service	Feature
Application Gateway	Resolves private endpoints using custom DNS.
Application Gateway	TLS / TCP Proxy.

Running the Tests

Prerequisites

Onboqard to Private Application Gateway deployment and TLS Proxy previews:

az feature register --name EnableApplicationGatewayNetworkIsolation --namespace Microsoft.Network
az feature register --name AllowApplicationGatewayTlsProxy --namespace Microsoft.Network

Deploy the Solution

By running the following command, you will deploy the solution to your Azure subscription.

terraform init
terraform apply

Checking Tests Results

Once the solution is deployed, you can download the tests results (TestResults.trx) with the following commands:

PowerShell:

$resultsShareKey=$(terraform output -raw results_share_key)
$resultsShareName=$(terraform output -raw results_share_name)
$resultsAccountName=$(terraform output -raw results_account_name)
$resultsFile=$(terraform output -raw results_file)
$aciStorageContext = New-AzStorageContext -StorageAccountName $resultsAccountName -StorageAccountKey $resultsShareKey
Get-AzStorageFileContent -ShareName $resultsShareName -Path $resultsFile -Context $aciStorageContext -Destination ".\report.trx" -Force

Azure CLI:

$resultsShareKey=$(terraform output -raw results_share_key)
$resultsShareName=$(terraform output -raw results_share_name)
$resultsAccountName=$(terraform output -raw results_account_name)
$resultsFile=$(terraform output -raw results_file)
az storage file download --account-key $resultsShareKey --account-name $resultsAccountName --share-name $resultsShareName --path $resultsFile

Checking Container Logs

PowerShell:

$resourceGroup=$(terraform output -raw resource_group)
$containerGroup=$(terraform output -raw contaner_group_name)
$containerName=$(terraform output -raw container_name)
Get-AzContainerInstanceLog -ResourceGroupName $resourceGroup -ContainerGroupName $containerGroup -ContainerName $containerName

Azure CLI:

$resourceGroup=$(terraform output -raw resource_group)
$containerGroup=$(terraform output -raw contaner_group_name)
$containerName=$(terraform output -raw container_name)
az container logs --resource-group $resourceGroup --name $containerGroup --container-name $containerName

FAQ

Where are the services deployed?

Poperty	Default Value	Terraform Variable	Required
Resource Group	rg-agw-pep	resource_group	[ ]
Region	westeurope	--------------	[ ]

Where are the Terraform modules documented?

Please refer to the Terraform Modules for more information.

Contributing

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This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact [email protected] with any additional questions or comments.

Trademarks

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