When you want to install the BGInfo VM extension during the Azure VM deployment through an ARM template, then you have to add the following lines to your template.
{ "apiVersion": "2015-06-15", "type": "Microsoft.Compute/virtualMachines/extensions", "name": "[concat(variables('vmName'),'/', parameters('vmBGInfo'))]", "location": "[parameters('location')]", "dependsOn": [ "[concat('Microsoft.Compute/virtualMachines/', variables('vmName'))]" ], "properties": { "publisher": "Microsoft.Compute", "type": "BGInfo", "typeHandlerVersion": "2.1", "settings": {}, "protectedSettings": null } }
For your template you have to customize the properties name, location and dependsOn. The lines have to be placed under resources after the VM definition in your template.
After a successful deployment you should see the informations provided by the BGInfo extension at your first RDP login.