AZURE ARM Templates. The parameter LinuxFxVersion has an invalid value [duplicate] - azure

Question

I've set-up an App Service using the following ARM template snippet:
{
"name": "[variables('webBackEnd')]",
"type": "Microsoft.Web/sites",
"location": "[parameters('location')]",
"apiVersion": "2015-08-01",
"dependsOn": [
"[resourceId('Microsoft.Web/serverfarms', parameters('hostingPlanName'))]"
],
"tags": {
"[concat('hidden-related:', resourceId('Microsoft.Web/serverfarms', parameters('hostingPlanName')))]": "Resource",
"displayName": "BackendWebApp"
},
"properties": {
"name": "[variables('webBackEnd')]",
"serverFarmId": "[resourceId('Microsoft.Web/serverfarms', parameters('hostingPlanName'))]"
}
},
This will deploy an App Service. However, by default, it will be setup to use the .Net Framework. Below is a view from my Azure Portal:
In order to run my ASP.Net Core-based web server, I have to manually switch the Stack Settings from ".Net" to ".Net Core". It's a trivial thing to do, but I'd much rather configure it correctly through the ARM template. I searched Microsoft's docs but was unable to find the correct property. How does one go about to do this?

Answer 1

here's how an example web app looks when created from the portal:
{
"apiVersion": "2018-02-01",
"name": "[parameters('name')]",
"type": "Microsoft.Web/sites",
"location": "[parameters('location')]",
"properties": {
"name": "[parameters('name')]",
"siteConfig": {
"appSettings": [],
"metadata": [
{
"name": "CURRENT_STACK",
"value": "[parameters('currentStack')]"
}
]
},
// redacted some values
}
},
and the current stack value is dotnetcore

Answer 2

The accepted answer didn't work for me. I began my own investigation and finished with this code, which works in my case.
"type": "Microsoft.Web/sites",
"apiVersion": "2018-11-01",
"name": "[parameters('site_name')]",
"location": "[resourceGroup().location]",
.........................................
"resources": [
{
"name": "metadata",
"type": "config",
"apiVersion": "2018-11-01",
"dependsOn": [
"[resourceId('Microsoft.Web/sites', parameters('site_name'))]"
],
"tags": {
},
"properties": {
"CURRENT_STACK": "dotnetcore"
}
}
]