Change web app .NET framework version with ARM template - .net-core

Question

I'm updating an existing web app to .NET 5. There is an ARM template that describes the web app configuration.
In the ARM template I have added
"netFrameworkVersion": "v5.0",
inside the Microsoft.Web/sites/config properties object.
The ARM template deployment succeeds, but the web app configuration is not changed from .NET Core 3.1 to .NET 5.
Oddly, when I look at the Azure Resource manager, it does contain the net netFrameworkVersion value.
This configuration is what I'm trying to change to .NET 5:
Am I missing a setting, or is it not possible to update the .NET version using an ARM template?

Answer 1

The answer for me was setting the property netFrameworkVersion to v6.0. No other change was necessary.
This is the partial ARM template, the section changed:
{
"name": "[parameters('webSiteName')]",
"type": "Microsoft.Web/sites",
"apiVersion": "2019-08-01",
"location": "[parameters('location')]",
"tags": {
"[concat('hidden-related:', resourceId('Microsoft.Web/serverfarms', variables('hostingPlanName')))]": "empty"
},
"dependsOn": [
"[variables('hostingPlanName')]",
"[variables('appInsightsName')]"
],
"properties": {
"name": "[parameters('webSiteName')]",
"serverFarmId": "[resourceId('Microsoft.Web/serverfarms', variables('hostingPlanName'))]",
"siteConfig": {
"appSettings": [
{
"name": "APPINSIGHTS_INSTRUMENTATIONKEY",
"value": "[reference(resourceId('Microsoft.Insights/components/', variables('appInsightsName')), '2020-02-02-preview').InstrumentationKey]"
},
{
"name": "APPLICATIONINSIGHTS_CONNECTION_STRING",
"value": "[reference(resourceId('Microsoft.Insights/components', variables('appInsightsName')), '2020-02-02-preview').ConnectionString]"
}
],
"connectionStrings": [
{
"name": "DefaultConnection",
"connectionString": "[concat('Data Source=tcp:', reference(resourceId('Microsoft.Sql/servers/', variables('sqlServerName'))).fullyQualifiedDomainName, ',1433;Initial Catalog=', parameters('databaseName'), ';User Id=', parameters('databaseUserLogin'), '#', reference(resourceId('Microsoft.Sql/servers/', variables('sqlServerName'))).fullyQualifiedDomainName, ';Password=', parameters('databaseUserPassword'), ';')]",
"type": "SQLAzure"
}
],
"ftpsState": "FtpsOnly",
"netFrameworkVersion": "v6.0"
},
"httpsOnly": true
}
}
You can find the full resource and ARM template at: https://github.com/feliperomero3/MoneySmart/blob/e2210eb6217eb6e06a299870acaf115d2e50c6a5/AzureResourceGroup/azuredeploy.json

Answer 2

Except for the netFrameworkVersion you need to change, also you need to add another resource to the resources in your template, just add it like below, it works fine on my side.
Note: It is for the web app whose OS is Windows.
{
"type": "Microsoft.Web/sites/config",
"apiVersion": "2018-11-01",
"name": "[concat(parameters('webapp_name'), '/metadata')]",
"location": "Central US",
"dependsOn": [
"[resourceId('Microsoft.Web/sites', parameters('webapp_name'))]"
],
"properties": {
"CURRENT_STACK": "dotnet"
}
}
My complete sample:
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"webapp_name": {
"defaultValue": "joyweb11",
"type": "String"
},
"serviceplan_resourceid": {
"defaultValue": "/subscriptions/xxxxx/resourceGroups/xxxx/providers/Microsoft.Web/serverfarms/joyplan",
"type": "String"
}
},
"variables": {},
"resources": [
{
"type": "Microsoft.Web/sites",
"apiVersion": "2018-11-01",
"name": "[parameters('webapp_name')]",
"location": "Central US",
"tags": {},
"kind": "app",
"properties": {
"enabled": true,
"hostNameSslStates": [
{
"name": "[concat(parameters('webapp_name'), '.azurewebsites.net')]",
"sslState": "Disabled",
"hostType": "Standard"
},
{
"name": "[concat(parameters('webapp_name'), '.scm.azurewebsites.net')]",
"sslState": "Disabled",
"hostType": "Repository"
}
],
"serverFarmId": "[parameters('serviceplan_resourceid')]",
"reserved": false,
"isXenon": false,
"hyperV": false,
"siteConfig": {},
"scmSiteAlsoStopped": false,
"clientAffinityEnabled": true,
"clientCertEnabled": false,
"hostNamesDisabled": false,
"containerSize": 0,
"dailyMemoryTimeQuota": 0,
"httpsOnly": false,
"redundancyMode": "None"
}
},
{
"type": "Microsoft.Web/sites/config",
"apiVersion": "2018-11-01",
"name": "[concat(parameters('webapp_name'), '/web')]",
"location": "Central US",
"dependsOn": [
"[resourceId('Microsoft.Web/sites', parameters('webapp_name'))]"
],
"tags": {
},
"properties": {
"numberOfWorkers": 1,
"defaultDocuments": [
"Default.htm",
"Default.html",
"Default.asp",
"index.htm",
"index.html",
"iisstart.htm",
"default.aspx",
"index.php",
"hostingstart.html"
],
"netFrameworkVersion": "v5.0",
"requestTracingEnabled": false,
"remoteDebuggingEnabled": false,
"remoteDebuggingVersion": "VS2019",
"httpLoggingEnabled": false,
"logsDirectorySizeLimit": 35,
"detailedErrorLoggingEnabled": false,
"publishingUsername": "$joyweb11",
"azureStorageAccounts": {},
"scmType": "None",
"use32BitWorkerProcess": true,
"webSocketsEnabled": false,
"alwaysOn": true,
"managedPipelineMode": "Integrated",
"virtualApplications": [
{
"virtualPath": "/",
"physicalPath": "site\\wwwroot",
"preloadEnabled": true
}
],
"loadBalancing": "LeastRequests",
"experiments": {
"rampUpRules": []
},
"autoHealEnabled": false,
"localMySqlEnabled": false,
"ipSecurityRestrictions": [
{
"ipAddress": "Any",
"action": "Allow",
"priority": 1,
"name": "Allow all",
"description": "Allow all access"
}
],
"scmIpSecurityRestrictions": [
{
"ipAddress": "Any",
"action": "Allow",
"priority": 1,
"name": "Allow all",
"description": "Allow all access"
}
],
"scmIpSecurityRestrictionsUseMain": false,
"http20Enabled": false,
"minTlsVersion": "1.2",
"ftpsState": "AllAllowed",
"reservedInstanceCount": 0
}
},
{
"type": "Microsoft.Web/sites/hostNameBindings",
"apiVersion": "2018-11-01",
"name": "[concat(parameters('webapp_name'), '/', parameters('webapp_name'), '.azurewebsites.net')]",
"location": "Central US",
"dependsOn": [
"[resourceId('Microsoft.Web/sites', parameters('webapp_name'))]"
],
"properties": {
"siteName": "[parameters('webapp_name')]",
"hostNameType": "Verified"
}
},
{
"type": "Microsoft.Web/sites/config",
"apiVersion": "2018-11-01",
"name": "[concat(parameters('webapp_name'), '/metadata')]",
"location": "Central US",
"dependsOn": [
"[resourceId('Microsoft.Web/sites', parameters('webapp_name'))]"
],
"properties": {
"CURRENT_STACK": "dotnet"
}
}
]
}