Terraform – Import Azure Resources

One of the first uses I’ll have for Terraform in my work will be adding resources to an existing environment – an environment for which Terraform has no state information. This means when I’m declaring the new VMs and want to tie it to a Resource Group, Terraform won’t have a matching resource for that.

Today I’ve been playing around with Terraform import in my sandbox to become familiar with the process. In my sandbox I have an existing Resource Group, Virtual Network, and Subnet. I intended to add a simple network interface, tied to an already-existing subnet.

To begin, I declared my existing resources in my .TF file as I would want them to exist (technically matching how they exist right now):

resource "azurerm_resource_group" "Client_1" {  
 name = "Client_1"
 location = "${var.location}"
 }
 
resource "azurerm_virtual_network" "Client1Network" {
 name = "Client1Network"
 address_space = ["10.1.0.0/16"]
 location = "${var.location}"
 resource_group_name = "${azurerm_resource_group.Client_1.name}"
 }
 
resource "azurerm_subnet" "Web" {
 name = "Web"
 resource_group_name = "${azurerm_resource_group.Client_1.name}"
 virtual_network_name = "${azurerm_virtual_network.Client1Network.name}"
 address_prefix = "10.1.10.0/24"
 }

Then for each of them I gathered the Resource ID in Azure. For the resource group and virtual network this was simple enough; find the Properties pane and copy the string that was there:

For the Subnet, there wasn’t an easy GUI reference that I could find, so I turned to Azure PowerShell, which output the ID I needed:

$vmnet = get-azurermVirtualnetwork | where {$_.Name -eq "Client1Network" }
 
get-azurermvirtualnetworksubnetconfig -virtualnetwork $vmnet

Then I used the Terraform “import” command along with the resource declaration and name in my file, and the resource ID from Azure:

terraform import azurerm_resource_group.Client_1 /subscriptions/f745d13d/resourceGroups/Client_1/providers/Microsoft.Network/virtualNetworks/Client1Network

I repeated the process for the resource group, virtual network, and subnet.

Then I added the resource declartaion in my .TF file for the network interface I wanted to add:

resource "azurerm_network_interface" "testNIC" {
 name = "testNIC"
 location = "${var.location}"
 resource_group_name = "${azurerm_resource_group.Client_1.name}"
 ip_configuration {
 name = "testconfiguration1"
 subnet_id = "${azurerm_subnet.Web.id}"
 private_ip_address_allocation = "dynamic"
 }
}

Then I performed a “terraform plan”, which showed me the resource it detected needing to be created:

Once I completed the “terraform apply”, the resource was created and visible within my Azure portal.