Quickstart: Create an internal load balancer to load balance VMs by using an ARM template

This quickstart describes how to use an Azure Resource Manager template (ARM template) to create an internal Azure load balancer.

An ARM template is a JavaScript Object Notation (JSON) file that defines the infrastructure and configuration for your project. The template uses declarative syntax. In declarative syntax, you describe your intended deployment without writing the sequence of programming commands to create the deployment.

If your environment meets the prerequisites and you're familiar with using ARM templates, select the Deploy to Azure button. The template will open in the Azure portal.

Deploy to Azure

Prerequisites

If you don't have an Azure subscription, create a free account before you begin.

Review the template

The template used in this quickstart is from the Azure Quickstart Templates.

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "metadata": {
    "_generator": {
      "name": "bicep",
      "version": "0.5.6.12127",
      "templateHash": "12604669370283105560"
    }
  },
  "parameters": {
    "adminUsername": {
      "type": "string",
      "metadata": {
        "description": "Admin username"
      }
    },
    "adminPassword": {
      "type": "secureString",
      "metadata": {
        "description": "Admin password"
      }
    },
    "vmNamePrefix": {
      "type": "string",
      "defaultValue": "BackendVM",
      "metadata": {
        "description": "Prefix to use for VM names"
      }
    },
    "location": {
      "type": "string",
      "defaultValue": "[resourceGroup().location]",
      "metadata": {
        "description": "Location for all resources."
      }
    },
    "vmSize": {
      "type": "string",
      "defaultValue": "Standard_D2s_v3",
      "metadata": {
        "description": "Size of the virtual machines"
      }
    }
  },
  "variables": {
    "availabilitySetName": "AvSet",
    "storageAccountType": "Standard_LRS",
    "storageAccountName": "[uniqueString(resourceGroup().id)]",
    "virtualNetworkName": "vNet",
    "subnetName": "backendSubnet",
    "loadBalancerName": "ilb",
    "networkInterfaceName": "nic",
    "subnetRef": "[resourceId('Microsoft.Network/virtualNetworks/subnets', variables('virtualNetworkName'), variables('subnetName'))]",
    "numberOfInstances": 2
  },
  "resources": [
    {
      "type": "Microsoft.Storage/storageAccounts",
      "apiVersion": "2021-08-01",
      "name": "[variables('storageAccountName')]",
      "location": "[parameters('location')]",
      "sku": {
        "name": "[variables('storageAccountType')]"
      },
      "kind": "StorageV2"
    },
    {
      "type": "Microsoft.Compute/availabilitySets",
      "apiVersion": "2021-11-01",
      "name": "[variables('availabilitySetName')]",
      "location": "[parameters('location')]",
      "sku": {
        "name": "Aligned"
      },
      "properties": {
        "platformUpdateDomainCount": 2,
        "platformFaultDomainCount": 2
      }
    },
    {
      "type": "Microsoft.Network/virtualNetworks",
      "apiVersion": "2021-05-01",
      "name": "[variables('virtualNetworkName')]",
      "location": "[parameters('location')]",
      "properties": {
        "addressSpace": {
          "addressPrefixes": [
            "10.0.0.0/16"
          ]
        },
        "subnets": [
          {
            "name": "[variables('subnetName')]",
            "properties": {
              "addressPrefix": "10.0.2.0/24"
            }
          }
        ]
      }
    },
    {
      "copy": {
        "name": "networkInterface",
        "count": "[length(range(0, variables('numberOfInstances')))]"
      },
      "type": "Microsoft.Network/networkInterfaces",
      "apiVersion": "2021-05-01",
      "name": "[format('{0}{1}', variables('networkInterfaceName'), range(0, variables('numberOfInstances'))[copyIndex()])]",
      "location": "[parameters('location')]",
      "properties": {
        "ipConfigurations": [
          {
            "name": "ipconfig1",
            "properties": {
              "privateIPAllocationMethod": "Dynamic",
              "subnet": {
                "id": "[variables('subnetRef')]"
              },
              "loadBalancerBackendAddressPools": [
                {
                  "id": "[resourceId('Microsoft.Network/loadBalancers/backendAddressPools', variables('loadBalancerName'), 'BackendPool1')]"
                }
              ]
            }
          }
        ]
      },
      "dependsOn": [
        "[resourceId('Microsoft.Network/loadBalancers', variables('loadBalancerName'))]",
        "[resourceId('Microsoft.Network/virtualNetworks', variables('virtualNetworkName'))]"
      ]
    },
    {
      "type": "Microsoft.Network/loadBalancers",
      "apiVersion": "2021-05-01",
      "name": "[variables('loadBalancerName')]",
      "location": "[parameters('location')]",
      "sku": {
        "name": "Standard"
      },
      "properties": {
        "frontendIPConfigurations": [
          {
            "properties": {
              "subnet": {
                "id": "[variables('subnetRef')]"
              },
              "privateIPAddress": "10.0.2.6",
              "privateIPAllocationMethod": "Static"
            },
            "name": "LoadBalancerFrontend"
          }
        ],
        "backendAddressPools": [
          {
            "name": "BackendPool1"
          }
        ],
        "loadBalancingRules": [
          {
            "properties": {
              "frontendIPConfiguration": {
                "id": "[resourceId('Microsoft.Network/loadBalancers/frontendIpConfigurations', variables('loadBalancerName'), 'LoadBalancerFrontend')]"
              },
              "backendAddressPool": {
                "id": "[resourceId('Microsoft.Network/loadBalancers/backendAddressPools', variables('loadBalancerName'), 'BackendPool1')]"
              },
              "probe": {
                "id": "[resourceId('Microsoft.Network/loadBalancers/probes', variables('loadBalancerName'), 'lbprobe')]"
              },
              "protocol": "Tcp",
              "frontendPort": 80,
              "backendPort": 80,
              "idleTimeoutInMinutes": 15
            },
            "name": "lbrule"
          }
        ],
        "probes": [
          {
            "properties": {
              "protocol": "Tcp",
              "port": 80,
              "intervalInSeconds": 15,
              "numberOfProbes": 2
            },
            "name": "lbprobe"
          }
        ]
      },
      "dependsOn": [
        "[resourceId('Microsoft.Network/virtualNetworks', variables('virtualNetworkName'))]"
      ]
    },
    {
      "copy": {
        "name": "vm",
        "count": "[length(range(0, variables('numberOfInstances')))]"
      },
      "type": "Microsoft.Compute/virtualMachines",
      "apiVersion": "2021-11-01",
      "name": "[format('{0}{1}', parameters('vmNamePrefix'), range(0, variables('numberOfInstances'))[copyIndex()])]",
      "location": "[parameters('location')]",
      "properties": {
        "availabilitySet": {
          "id": "[resourceId('Microsoft.Compute/availabilitySets', variables('availabilitySetName'))]"
        },
        "hardwareProfile": {
          "vmSize": "[parameters('vmSize')]"
        },
        "osProfile": {
          "computerName": "[format('{0}{1}', parameters('vmNamePrefix'), range(0, variables('numberOfInstances'))[copyIndex()])]",
          "adminUsername": "[parameters('adminUsername')]",
          "adminPassword": "[parameters('adminPassword')]"
        },
        "storageProfile": {
          "imageReference": {
            "publisher": "MicrosoftWindowsServer",
            "offer": "WindowsServer",
            "sku": "2019-Datacenter",
            "version": "latest"
          },
          "osDisk": {
            "createOption": "FromImage"
          }
        },
        "networkProfile": {
          "networkInterfaces": [
            {
              "id": "[resourceId('Microsoft.Network/networkInterfaces', format('{0}{1}', variables('networkInterfaceName'), range(0, variables('numberOfInstances'))[range(0, variables('numberOfInstances'))[copyIndex()]]))]"
            }
          ]
        },
        "diagnosticsProfile": {
          "bootDiagnostics": {
            "enabled": true,
            "storageUri": "[reference(resourceId('Microsoft.Storage/storageAccounts', variables('storageAccountName'))).primaryEndpoints.blob]"
          }
        }
      },
      "dependsOn": [
        "[resourceId('Microsoft.Compute/availabilitySets', variables('availabilitySetName'))]",
        "[resourceId('Microsoft.Network/networkInterfaces', format('{0}{1}', variables('networkInterfaceName'), range(0, variables('numberOfInstances'))[range(0, variables('numberOfInstances'))[copyIndex()]]))]",
        "[resourceId('Microsoft.Storage/storageAccounts', variables('storageAccountName'))]"
      ]
    }
  ]
}

Multiple Azure resources have been defined in the template:

To find more templates that are related to Azure Load Balancer, see Azure Quickstart Templates.

Deploy the template

Azure CLI

read -p "Enter the location (i.e. westcentralus): " location
resourceGroupName="myResourceGroupLB"
templateUri="https://raw.githubusercontent.com/Azure/azure-quickstart-templates/master/quickstarts/microsoft.compute/2-vms-internal-load-balancer/azuredeploy.json"

az group create \
--name $resourceGroupName \
--location $location

az deployment group create \
--resource-group $resourceGroupName \
--template-uri  $templateUri

Review deployed resources

  1. Sign in to the Azure portal.

  2. Select Resource groups from the left pane.

  3. Select the resource group that you created in the previous section. The default resource group name is myResourceGroupLB

  4. Verify the following resources were created in the resource group:

User Azure portal to verify creation of resources.

Clean up resources

When no longer needed, you can use the az group delete command to remove the resource group and all resources contained within.

  az group delete \
    --name myResourceGroupLB

Next steps

For a step-by-step tutorial that guides you through the process of creating a template, see: