Environment Variables¶

The Vagrantfile injects these environment variables into each provisioning script. They are derived from cluster.yaml and computed at runtime.

Variables Available in All Scripts¶

Variable	Source	Example Value	Description
`PRIMARY_IP`	Current node's `ip` field	`192.168.56.10`	The private network IP of the current node
`NODE_NAME`	Current node's `name` field	`controlplane`	Hostname of the current node
`NODE_INDEX`	Position in `nodes` array	`0`	Zero-based index of the current node
`TOTAL_NODES`	Length of `nodes` array	`4`	Total number of nodes in the cluster
`WORKER_COUNT`	Count of worker nodes	`3`	Number of worker nodes
`PHASE`	Current provisioning phase	`1`	Current script phase number (1, 2, or 3)
`PHASE_TOTAL`	Total phases	`3`	Always `3`

Variables Available in Phase 2+ Scripts¶

Variable	Source	Example Value	Description
`POD_CIDR`	`cluster.pod_cidr`	`10.244.0.0/16`	Pod network CIDR range
`SERVICE_CIDR`	`cluster.service_cidr`	`10.96.0.0/16`	Service network CIDR range
`CALICO_VERSION`	`cluster.calico_version`	`v3.31.5`	Calico CNI version to deploy

Control Plane–Only Variable¶

Variable	Source	Example Value	Description
`CONTROL_PLANE_IP`	`ip` of the controlplane node	`192.168.56.10`	Used as `--apiserver-advertise-address`

How Variables Are Injected¶

The Vagrantfile uses Vagrant's shell provisioner with inline env parameter:

node_config.vm.provision "shell",
  path: "scripts/01-common.sh",
  env: {
    "PRIMARY_IP"   => node["ip"],
    "NODE_NAME"    => node["name"],
    "NODE_INDEX"   => index.to_s,
    "TOTAL_NODES"  => nodes.length.to_s,
    "WORKER_COUNT" => worker_count.to_s,
    "PHASE"        => "1",
    "PHASE_TOTAL"  => "3"
  }

Scripts access these as standard environment variables:

echo "Running on node: $NODE_NAME at IP: $PRIMARY_IP"

System Files Written by Scripts¶

Several scripts write values to persistent system files:

File	Written By	Content
`/etc/environment`	`01-common.sh`	`PRIMARY_IP=<ip>`
`/etc/modules-load.d/k8s.conf`	`01-common.sh`	`overlay` and `br_netfilter`
`/etc/sysctl.d/k8s.conf`	`01-common.sh`	Bridge and IP forwarding rules
`/etc/default/kubelet`	`02-kubernetes.sh`	`KUBELET_EXTRA_ARGS=--node-ip=<ip>`
`/vagrant/join-command.sh`	`03-controlplane.sh`	kubeadm join command