kubernetes/kops · error

must specify cloud

Error message

must specify cloud

What it means

addNodeController switches on opt.Cloud to pick a NodeIdentifier; when opt.Cloud is the empty string it returns the plain error "must specify cloud". kops-controller cannot choose a cloud-specific node identity provider without knowing the cloud, so startup fails fast.

Source

Thrown at cmd/kops-controller/main.go:377

		identifier, err = nodeidentityscw.New(opt.CacheNodeidentityInfo)
		if err != nil {
			return fmt.Errorf("error building node identifier: %w", err)
		}

	case "metal":
		identifier, err = nodeidentitymetal.New()
		if err != nil {
			return fmt.Errorf("error building metal node identifier: %w", err)
		}

	case "linode":
		identifier, err = nodeidentitylinode.New(opt.CacheNodeidentityInfo)
		if err != nil {
			return fmt.Errorf("error building linode node identifier: %w", err)
		}

	case "":
		return fmt.Errorf("must specify cloud")

	default:
		return fmt.Errorf("identifier for cloud %q not implemented", opt.Cloud)
	}

	nodeController, err := controllers.NewNodeReconciler(mgr, identifier)
	if err != nil {
		return err
	}
	if err := nodeController.SetupWithManager(mgr); err != nil {
		return err
	}

	return nil
}

// Reconciler is the interface for a standard Reconciler.
type Reconciler interface {

View on GitHub (pinned to 4c8573c808)

Solutions

1. Add --cloud=<provider> (e.g. aws, gce, openstack, azure, hetzner, digitalocean, scaleway, metal, linode) to the kops-controller invocation
2. If relying on the CLOUD environment variable, ensure it is set in the pod/container spec
3. Re-deploy the controller with the complete flag set copied from a known-good configuration

Example fix

// before (pod args)
args:
  - kops-controller
  - --config-dir=/etc/kubernetes/kops-controller/
// after
args:
  - kops-controller
  - --cloud=aws
  - --config-dir=/etc/kubernetes/kops-controller/

// validate args before launching
if opt.Cloud == "" {
	log.Error(nil, "--cloud flag is required")
	os.Exit(2)
}

if err := addNodeController(context, opt); err != nil {
	log.Error(err, "failed to add node controller")
	os.Exit(1)
}

When it happens

Trigger: Launching kops-controller without the --cloud flag and without CLOUD set in the environment, so options resolve Cloud to "".

Common situations: Deployment manifests (Deployment YAML, systemd unit, Helm values) missing the --cloud flag; environment variable not propagated into the container; operator upgraded kOps and dropped the flag from their run command.

Understand the failure class

Background: "--flag is required" and "must specify" CLI errors: how missing-required-flag validation works and how to fix it — this error's family across 20 libraries.

Related errors

• identifier for cloud %q not implemented
• clientset is not initialized
• error building metal node identifier: %w
• error building linode node identifier: %w
• kOps IPAM controller is not supported on cloud %q

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/cfdbf9051c359cb2. Report an issue: GitHub.