.

    Create the Resource Group

    resource "azurerm_resource_group" "example" {
  name     = "peeredvnets-rg"
  location = "West US"
}

    Create our Virtual Network and Subnet

    resource "azurerm_virtual_network" "example" {
  name                = "test"
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name
  address_space       = ["10.0.0.0/16"]
}

resource "azurerm_subnet" "example" {
  name                 = "GatewaySubnet"
  resource_group_name  = azurerm_resource_group.example.name
  virtual_network_name = azurerm_virtual_network.example.name
  address_prefixes     = ["10.0.1.0/24"]
}

    Create the Public IP address

    resource "azurerm_public_ip" "example" {
  name                = "test"
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name
  allocation_method   = "Dynamic"
}

    Create a Virtual Network Gateway and connection

    resource "azurerm_virtual_network_gateway" "example" {
  name                = "test"
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name

  type     = "Vpn"
  vpn_type = "RouteBased"

  active_active = false
  enable_bgp    = false
  sku           = "Basic"

  ip_configuration {
    public_ip_address_id          = azurerm_public_ip.example.id
    private_ip_address_allocation = "Dynamic"
    subnet_id                     = azurerm_subnet.example.id
  }
}

resource "azurerm_virtual_network_gateway_connection" "onpremise" {
  name                = "onpremise"
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name

  type                       = "IPsec"
  virtual_network_gateway_id = azurerm_virtual_network_gateway.example.id
  local_network_gateway_id   = azurerm_local_network_gateway.onpremise.id

  shared_key = "4-v3ry-53cr37-1p53c-5h4r3d-k3y"
}}

    Generate certificates