lima-vm/lima · error

field `mountType` must be %#q for WSL2 driver, got %#q

Error message

field `mountType` must be %#q for WSL2 driver, got %#q

What it means

The WSL2 driver only supports the WSL reverse-sshfs/9p style mount; validateConfig rejects any explicitly set mountType other than WSLMount. This catches YAML configs written for qemu/vz being reused with the WSL2 driver.

Source

Thrown at pkg/driver/wsl2/wsl_driver_windows.go:102

	l.Instance = inst
	l.SSHLocalPort = inst.SSHLocalPort

	return &driver.ConfiguredDriver{
		Driver: l,
	}, nil
}

func (l *LimaWslDriver) Validate(ctx context.Context) error {
	return validateConfig(ctx, l.Instance.Config)
}

func validateConfig(_ context.Context, cfg *limatype.LimaYAML) error {
	if cfg == nil {
		return errors.New("configuration is nil")
	}
	if cfg.MountType != nil && *cfg.MountType != limatype.WSLMount {
		return fmt.Errorf("field `mountType` must be %#q for WSL2 driver, got %#q", limatype.WSLMount, *cfg.MountType)
	}
	// TODO: revise this list for WSL2
	if cfg.VMType != nil {
		if unknown := reflectutil.UnknownNonEmptyFields(cfg, knownYamlProperties...); len(unknown) > 0 {
			logrus.Warnf("Ignoring: vmType %s: %+v", *cfg.VMType, unknown)
		}
	}

	if cfg.OS != nil && *cfg.OS == limatype.WINDOWS {
		return errors.New("currently Windows guest OS is only supported on QEMU")
	}

	if !limatype.IsNativeArch(*cfg.Arch) {
		return fmt.Errorf("unsupported arch: %#q", *cfg.Arch)
	}

	if cfg.TPM != nil && *cfg.TPM {
		return errors.New("field `tpm` is not supported on WSL2 driver")

View on GitHub (pinned to dd909d0973)

Solutions

1. Remove the `mountType` line from the YAML so the WSL2 default applies
2. Or set `mountType: wsl2` explicitly in lima.yaml
3. Re-run `limactl start`; use `limactl edit` to fix an existing instance's config

Example fix

// before
mountType: virtiofs
// after
mountType: wsl2   # or omit entirely; WSL2 driver defaults to wsl2

// Validate mountType compatibility before starting a wsl2 instance
const cfg = yaml.parse(fs.readFileSync('lima.yaml', 'utf8'));
if (cfg.vmType === 'wsl2' && cfg.mountType && cfg.mountType !== 'wsl2') {
  throw new Error(`mountType ${cfg.mountType} unsupported for wsl2; use wsl2 or remove the field`);
}

null

try {
  await limactlStart(inst);
} catch (e) {
  if (/mountType.*must be/.test(String(e))) {
    console.error('Fix lima.yaml: set mountType: wsl2 (or remove it) and retry');
  } else throw e;
}

When it happens

Trigger: lima.yaml contains `mountType: virtiofs` (or sshfs/9p/native) while vmType is wsl2; validateConfig runs during create/start validation and rejects the combination.

Common situations: Copying a macOS qemu/vz Lima YAML to a Windows WSL2 machine; explicitly setting virtiofs out of habit; templates defaulting to a non-WSL mount type.

Related errors

• the YAML is invalid, saved the buffer as %#q: %w
• field `vmOpts.qemu.minimumVersion` must be a semvar value, g
• configuration is nil
• failed to validate the instance YAML after filling defaults:
• invalid ssh local port %d

AI-assisted analysis of lima-vm/lima@dd909d0973 (2026-09-01). Data as JSON: /api/errors/c99d3da785dbb363. Report an issue: GitHub.