kubernetes/kops · error

name is required

Error message

name is required

What it means

A required-argument check in the toolbox clusterapi generate-machinedeployment command: the --name flag (which names the MachineDeployment and related objects) was left empty, so no object names can be derived.

Source

Thrown at pkg/commands/toolbox/clusterapi/generate_machinedeployment.go:101

	cmd.Flags().StringVar(&options.ClusterName, "cluster", options.ClusterName, "Name of cluster to join")
	cmd.Flags().StringVar(&options.Name, "name", options.Name, "Name of MachineDeployment (and other objects) to create")
	cmd.Flags().StringVar(&options.Namespace, "namespace", options.Namespace, "Namespace for objects")
	cmd.Flags().IntVar(&options.Replicas, "replicas", options.Replicas, "Number of replicas for MachineDeployment")
	cmd.Flags().StringArrayVar(&options.Zones, "zones", options.Zones, "Zones for the MachineDeployment (if not specified, will be deployed to all discovered zones in the cluster)")
	cmd.Flags().StringVar(&options.InstanceType, "instance-type", options.InstanceType, "Instance type for the MachineDeployment (if not specified, an arbitrary instance type from the instance groups will be used)")
	cmd.Flags().StringVar(&options.Subnet, "subnet", options.Subnet, "Subnet for the MachineDeployment (if not specified, an arbitrary subnet from the instance groups will be used)")
	cmd.Flags().StringVar(&options.Image, "image", options.Image, "Image for the MachineDeployment (if not specified, an arbitrary image from the instance groups will be used)")
	return cmd
}

func RunGenerateMachineDeployment(ctx context.Context, f commandutils.Factory, out io.Writer, options *GenerateMachineDeploymentOptions) error {
	log := klog.FromContext(ctx)

	if options.ClusterName == "" {
		return fmt.Errorf("cluster is required")
	}
	if options.Name == "" {
		return fmt.Errorf("name is required")
	}

	clientset, err := f.KopsClient()
	if err != nil {
		return err
	}

	cluster, err := clientset.GetCluster(ctx, options.ClusterName)
	if err != nil {
		return err
	}

	// TODO: Sync with LinkToSubnet and support ID
	subnet := options.Subnet
	if subnet == "" {
		subnets := sets.New[string]()
		for _, subnet := range cluster.Spec.Networking.Subnets {
			subnets.Insert(subnet.Name)

View on GitHub (pinned to 4c8573c808)

Solutions

1. Pass --name <machinedeployment-name> to the command.
2. Set options.Name explicitly when invoking programmatically.
3. Default the name in scripts, e.g. NAME="${NAME:-workers}".

Example fix

// before
opts := &GenerateMachineDeploymentOptions{ClusterName: "c1.k8s.local"}
RunGenerateMachineDeployment(ctx, f, out, opts) // name is required
// after
opts := &GenerateMachineDeploymentOptions{ClusterName: "c1.k8s.local", Name: "workers"}
RunGenerateMachineDeployment(ctx, f, out, opts)

if options == nil || options.Name == "" {
	return fmt.Errorf("name is required: pass --name <machinedeployment-name>")
}

func optsReady(o *GenerateMachineDeploymentOptions) bool {
	return o != nil && o.ClusterName != "" && o.Name != ""
}

if err := RunGenerateMachineDeployment(ctx, f, out, options); err != nil {
	if err.Error() == "name is required" {
		return fmt.Errorf("--name is required: %w", err)
	}
	return err
}

When it happens

Trigger: Running the toolbox clusterapi generate machinedeployment command without --name, or constructing GenerateMachineDeploymentOptions without setting Name.

Common situations: Omitting --name in CI automation; assuming the name is derived from the cluster; copying command examples that predate the required --name flag.

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

• cluster is required
• error creating kops config template: %w
• error creating gcp machine template: %w
• error building machine deployments: %w
• no subnets found in cluster %q

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/85e03f71d8f4ed03. Report an issue: GitHub.