ServerClaims

The ServerClaim Custom Resource Definition (CRD) is a Kubernetes resource used to claim ownership of a bare metal Server resource that is in the Available state. It allows users to specify the desired operating system image and ignition configuration for booting the server. The ServerClaimReconciler handles the allocation of servers to claims and manages the lifecycle of the claim and the server.

Example ServerClaim Resource

Claiming a Specific Server with Ignition Configuration:

apiVersion: metal.ironcore.dev/v1alpha1
kind: ServerClaim
metadata:
  name: my-server-claim
  namespace: default
spec:
  power: "On"
  serverRef:
    name: "my-server"
  image: "my-osimage:latest"
  ignitionSecretRef:
    name: "my-ignition-secret"

Claiming a Server Using a Selector:

apiVersion: metal.ironcore.dev/v1alpha1
kind: ServerClaim
metadata:
  name: selector-server-claim
  namespace: default
spec:
  power: "On"
  serverSelector:
    matchLabels:
      hardwareType: gpu-node
      location: datacenter-1
  image: my-osimage:latest
  ignitionSecretRef:
    name: my-ignition-secret

Reconciliation Process

• ServerBootConfiguration:

  • The ServerClaimReconciler creates a ServerBootConfiguration resource under the hood.
  • This resource specifies how the server should be booted, including the image and ignition configuration.

• State Transitions:

  • Available → Reserved: When a server is successfully claimed.
  • Reserved → Available: When the ServerClaim is deleted and the server's spec.reclaimPolicy is Recycle (the default).
  • Reserved → Released: When the ServerClaim is deleted and the server's spec.reclaimPolicy is Retain. The server stays in Released with spec.serverClaimRef set until an operator clears the reference, at which point it transitions back to Available.

• Release Process:

  • On claim deletion the server is powered off and its BootConfigurationRef is cleared.
  • With Recycle, spec.serverClaimRef is also removed automatically and the server returns to Available.
  • With Retain, spec.serverClaimRef is preserved so the binding can be inspected before the server is released back into the pool.