HetznerTerra/terraform/firewall.tf

resource "hcloud_firewall" "cluster" {
  name = "${var.cluster_name}-firewall"

  rule {
    description = "SSH"
    direction   = "in"
    protocol    = "tcp"
    port        = "22"
    source_ips  = var.allowed_ssh_ips
  }

  rule {
    description = "Kubernetes API"
    direction   = "in"
    protocol    = "tcp"
    port        = "6443"
    source_ips  = var.allowed_api_ips
  }

  rule {
    description = "Kubernetes API (internal)"
    direction   = "in"
    protocol    = "tcp"
    port        = "6443"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "k3s Supervisor"
    direction   = "in"
    protocol    = "tcp"
    port        = "9345"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "etcd Client"
    direction   = "in"
    protocol    = "tcp"
    port        = "2379"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "etcd Peer"
    direction   = "in"
    protocol    = "tcp"
    port        = "2380"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "Flannel VXLAN"
    direction   = "in"
    protocol    = "udp"
    port        = "8472"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "Kubelet"
    direction   = "in"
    protocol    = "tcp"
    port        = "10250"
    source_ips  = [var.subnet_cidr]
  }

  rule {
    description = "NodePorts"
    direction   = "in"
    protocol    = "tcp"
    port        = "30000-32767"
    source_ips  = ["0.0.0.0/0"]
  }

  rule {
    description = "ICMP"
    direction   = "in"
    protocol    = "icmp"
    source_ips  = ["0.0.0.0/0"]
  }

  apply_to {
    label_selector = "cluster=${var.cluster_name}"
  }
}