kubernetes/kops · error

error serializing keyset: %v

Error message

error serializing keyset: %v

What it means

serializeKeysetBundle encodes a keyset object (certificates/private keys) to YAML using the kops v1alpha2 scheme encoder. If encoder.Encode fails — due to an object that does not conform to the scheme, unsupported fields, or serializer registration problems — this wrapped error is returned to writeKeysetBundle.

Source

Thrown at upup/pkg/fi/vfs_castore.go:153

	acl, err := acls.GetACL(ctx, p, cluster)
	if err != nil {
		return err
	}
	return p.WriteFile(ctx, bytes.NewReader(objectData), acl)
}

// serializeKeysetBundle converts a Keyset bundle to yaml, for writing to VFS.
func serializeKeysetBundle(o *kops.Keyset) ([]byte, error) {
	var objectData bytes.Buffer
	codecs := kopscodecs.Codecs
	yaml, ok := runtime.SerializerInfoForMediaType(codecs.SupportedMediaTypes(), "application/yaml")
	if !ok {
		klog.Fatalf("no YAML serializer registered")
	}
	encoder := codecs.EncoderForVersion(yaml.Serializer, v1alpha2.SchemeGroupVersion)

	if err := encoder.Encode(o, &objectData); err != nil {
		return nil, fmt.Errorf("error serializing keyset: %v", err)
	}
	return objectData.Bytes(), nil
}

// ListKeysets implements CAStore::ListKeysets
func (c *VFSCAStore) ListKeysets() (map[string]*Keyset, error) {
	ctx := context.TODO()

	baseDir := c.basedir.Join("private")
	files, err := baseDir.ReadTree(ctx)
	if err != nil {
		return nil, fmt.Errorf("error reading directory %q: %v", baseDir, err)
	}

	keysets := map[string]*Keyset{}

	for _, f := range files {
		relativePath, err := vfs.RelativePath(baseDir, f)

View on GitHub (pinned to 4c8573c808)

Solutions

1. Run `kops export kubecfg` / upgrade the state store with a matching kops version so keysets conform to v1alpha2.
2. Inspect the wrapped error's message for the offending field/type and fix the keyset data.
3. Verify the keyset was loaded successfully (no nil Primary entries) before mirroring.
4. Ensure kops binary and state-store API versions are compatible; re-create the keyset if data is corrupt (e.g. via `kops replace` or re-issuing certs).

// Go: no pre-call validation hook; ensure keyset was loaded from the same kops API version
if keyset == nil || keyset.Primary == nil {
	return fmt.Errorf("keyset %s not loaded before serialization", name)
}

data, err := serializeKeysetBundle(...)
if err != nil {
	return fmt.Errorf("mirroring keyset %q failed: %w; check kops/state-store version compatibility", name, err)
}

When it happens

Trigger: writeKeysetBundle serializing a Keyset whose contents fail scheme encoding: keyset data loaded from an incompatible kops API version, nil/invalid internal objects, or a Keyset missing required fields that the v1alpha2 encoder enforces.

Common situations: Mirroring a CA store created by an older kops version into a newer binary whose encoder requires v1alpha2 objects; corrupted keyset files in the state store; a bug where a keyset was constructed without proper type metadata.

Related errors

• error marshaling yaml: %v
• error writing yaml to stdout: %v
• unable to marshal YAML: %v
• unable to marshal YAML: %v
• unable to marshal YAML: %v

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/9d491a316029b1e1. Report an issue: GitHub.