kubernetes/kops · error

error visiting containers: %w

Error message

error visiting containers: %w

What it means

After computing new args for an externally provided cloud-controller-manager addon, buildAddons walks the manifest containers with addon.VisitContainers to inject the args. This error wraps any failure from VisitContainers, typically a malformed manifest structure that cannot be traversed.

Source

Thrown at upup/pkg/fi/cloudup/bootstrapchannelbuilder/bootstrapchannelbuilder.go:931

				gkDaemonset := schema.GroupKind{Group: "apps", Kind: "DaemonSet"}
				for _, addon := range b.ClusterAddons {
					if addon.GroupVersionKind().GroupKind() == gkDaemonset &&
						addon.GetName() == "cloud-controller-manager" &&
						addon.GetNamespace() == "kube-system" {

						klog.Infof("replacing arguments in externally provided cloud-controller-manager")

						args, err := b.addonRenderer.CloudControllerConfigArgv()
						if err != nil {
							return nil, nil, fmt.Errorf("in TemplateFunction CloudControllerConfigArgv: %w", err)
						}

						if err := addon.VisitContainers(func(container map[string]interface{}) error {
							// TODO: Check name?
							container["args"] = args
							return nil
						}); err != nil {
							return nil, nil, fmt.Errorf("error visiting containers: %w", err)
						}
					}
				}
			}

			if useBuiltin {
				id := "k8s-1.23"
				location := key + "/" + id + ".yaml"
				addon := addons.Add(&channelsapi.AddonSpec{
					Name:     new(key),
					Manifest: new(location),
					Selector: map[string]string{"k8s-addon": key},
					Id:       id,
				})
				addon.BuildPrune = true
			}
		}
	}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Validate the CCM addon manifest is a standard Deployment/DaemonSet with containers
2. Fix or regenerate the addon manifest from upstream
3. Remove the external addon to fall back to kops builtin CCM
4. Compare the manifest with the structure kops expects (spec.template.spec.containers)

Example fix

// before: nonstandard manifest
kind: Pod
spec:
  containers: []
// after: standard workload shape
kind: DaemonSet
spec:
  template:
    spec:
      containers:
      - name: ccm

// Ensure the manifest has a traversable pod template before VisitContainers
var addon struct { Spec struct { Template struct { Spec struct { Containers []map[string]interface{} `json:"containers"` } `json:"spec"` } `json:"template"` } `json:"spec"` }
if err := yaml.Unmarshal(manifestBytes, &addon); err != nil || len(addon.Spec.Template.Spec.Containers) == 0 {
    return errors.New("CCM manifest lacks spec.template.spec.containers")
}

if err := addon.VisitContainers(setArgs); err != nil {
    return fmt.Errorf("manifest not walkable; regenerate CCM manifest: %w", err)
}

When it happens

Trigger: Building a cluster with an external CCM addon whose manifest is not a valid Kubernetes pod-template structure (missing spec.template.spec.containers or unexpected shapes) causing VisitContainers to return an error.

Common situations: Hand-crafted or third-party CCM manifests with unusual structure; YAML that decodes but lacks expected container lists; addon channel drift after kops changes the expected schema.

Related errors

• unable to find manifest %s
• failed to parse manifest: %w
• error loading channel %q: %v
• unhandled kind %q in %s
• cannot specify additional objects when multiple clusters are

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/41afdd4ad9a8b448. Report an issue: GitHub.