update-nic2.json

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "nicName": {
      "type": "string"
    },
    "SubnetRef": {
      "type": "string"
    },
    "privateIp": {
      "type": "string"
    },
    "FortinetTags": {
      "type": "object"
    },
    "NSGName": {
        "type": "string"
    }
  },
  "variables": {
  },
  "resources": [
    {
      "apiVersion": "2017-09-01",
      "dependsOn": [
      ],
      "tags": {
        "provider": "[toUpper(parameters('FortinetTags').provider)]"
      },
      "type": "Microsoft.Network/networkInterfaces",
      "name": "[parameters('nicName')]",
      "location": "[resourceGroup().location]",
      "properties": {
        "ipConfigurations": [
            {
              "name": "ipconfig1",
              "properties": {
                "privateIPAllocationMethod": "Static",
                "privateIPAddress": "[parameters('privateIp')]",
                "subnet": {
                  "id": "[parameters('SubnetRef')]"
                }
              }
            }
          ],
          "enableIPForwarding": true,
          "networkSecurityGroup": {
            "id": "[resourceID('Microsoft.Network/networkSecurityGroups/',parameters('NSGName'))]"
          }
      }
    }
  ],
  "outputs": {}
}