Terraform Rancher GKE Node network tag

HI All,

I’m able to build a VM with Rancher via Terraform on Google Cloud Platform and provision a GKE Cluster

All good but now I need to add the network tag of the Google Engine VMs to the firewall rule so the cattle-node-agents are able to talk back to rancher.

Tried different combinations

# Google Cloud Firewall rules for K8s Workers
resource "google_compute_firewall" "k8s-workers" {
  depends_on = [rancher2_cluster.mars-cluster]
  name    = "rancher-master-allow-workers"
  network = var.gcp_vpc
  enable_logging = true

  allow {
     protocol = "all"

  # Allow traffic from everywhere to instances with an rancher-server tag
  **source_tags   = [ ->>> network node tag <<<-]**
  target_tags   = ["rancher-master"]

Or else how to get th external / internal IPs of the nodes ?