hashicorp/nomad · error

invalid capacity_min: %v

Error message

invalid capacity_min: %v

What it means

After decoding the HCL volume spec, csiDecodeVolume extracts the `capacity_min` block/value and runs parseCapacityBytes on it. If that parser fails (the value is not an empty string and not a humanize-parseable byte size), the error is wrapped as `invalid capacity_min: <reason>`. It indicates the `capacity_min` field in the volume spec is not a valid byte-capacity value.

Source

Thrown at command/volume_register_csi.go:78

	}

	// Need to manually parse these fields
	delete(m, "capability")
	delete(m, "mount_options")
	delete(m, "capacity_max")
	delete(m, "capacity_min")
	delete(m, "topology_request")
	delete(m, "type")

	// Decode the rest
	err = mapstructure.WeakDecode(m, vol)
	if err != nil {
		return nil, err
	}

	capacityMin, err := parseCapacityBytes(list.Filter("capacity_min"))
	if err != nil {
		return nil, fmt.Errorf("invalid capacity_min: %v", err)
	}
	vol.RequestedCapacityMin = capacityMin
	capacityMax, err := parseCapacityBytes(list.Filter("capacity_max"))
	if err != nil {
		return nil, fmt.Errorf("invalid capacity_max: %v", err)
	}
	vol.RequestedCapacityMax = capacityMax

	capObj := list.Filter("capability")
	if len(capObj.Items) > 0 {

		for _, o := range capObj.Elem().Items {
			valid := []string{"access_mode", "attachment_mode"}
			if err := helper.CheckHCLKeys(o.Val, valid); err != nil {
				return nil, err
			}

			ot, ok := o.Val.(*ast.ObjectType)

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Set capacity_min to a value parseable by dustin/go-humanize.ParseBytes, e.g. "1GiB", "500MB", or a plain integer of bytes.
2. Check for typos or stray characters in the value (commas, units per second, placeholder text).
3. Remove the capacity_min key entirely if a default is acceptable (an empty value parses to 0).

Example fix

// before
capacity_min = "10 GB/s"
// after
capacity_min = "10GiB"

// pre-validate capacity_min locally
func validCapacity(v string) bool {
	if v == "" { return true }
	_, err := humanize.ParseBytes(strings.Trim(v, "\""))
	return err == nil
}
if !validCapacity(spec.CapacityMin) {
	return fmt.Errorf("capacity_min %q is not a valid byte size", spec.CapacityMin)
}

vol, err := csiDecodeVolume(f)
if err != nil {
	var inv *fmt.Errorf
	if strings.HasPrefix(err.Error(), "invalid capacity_min") {
		return fmt.Errorf("fix capacity_min to e.g. 10GiB: %v", err)
	}
	return err
}

When it happens

Trigger: `nomad volume register` with a spec whose `capacity_min` is set to a non-numeric or non-size string, e.g. capacity_min = "big", "10 gb/s", "1OGB" (letter O), or a nested block where a literal is expected.

Common situations: Typos in unit suffixes; copying examples with placeholder values; locale-formatted numbers like "1,000 MB"; unit confusion between humanize's accepted suffixes (KB/MB/GB, kiB/MiB/GiB) and free-form text.

Related errors

• invalid capacity_max: %v
• invalid capability: %v
• error parsing: root should be an object
• missing secret ID
• CSI.ControllerValidateVolume: VolumeID is required

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/1f13de37b5d0ca12. Report an issue: GitHub.