hashicorp/nomad · error

capacity_max (%d) must be larger than capacity_min (%d)

Error message

capacity_max (%d) must be larger than capacity_min (%d)

What it means

HostVolume.Validate found the requested maximum capacity smaller than the requested minimum; capacity_max must be greater than or equal to capacity_min for a coherent volume request.

Source

Thrown at nomad/structs/host_volumes.go:147

}

// Validate verifies that the submitted HostVolume spec has valid field values,
// without validating any changes or state (see ValidateUpdate).
func (hv *HostVolume) Validate() error {

	var mErr *multierror.Error

	if hv.ID != "" && !helper.IsUUID(hv.ID) {
		mErr = multierror.Append(mErr, fmt.Errorf("invalid ID %q", hv.ID))
	}

	if hv.Name == "" {
		mErr = multierror.Append(mErr, errors.New("missing name"))
	}

	if hv.RequestedCapacityMaxBytes < hv.RequestedCapacityMinBytes {
		mErr = multierror.Append(mErr, fmt.Errorf(
			"capacity_max (%d) must be larger than capacity_min (%d)",
			hv.RequestedCapacityMaxBytes, hv.RequestedCapacityMinBytes))
	}

	for _, cap := range hv.RequestedCapabilities {
		err := cap.Validate()
		if err != nil {
			mErr = multierror.Append(mErr, err)
		}
	}

	for _, constraint := range hv.Constraints {
		if err := constraint.Validate(); err != nil {
			mErr = multierror.Append(mErr, fmt.Errorf("invalid constraint: %v", err))
		}
		switch constraint.Operand {
		case ConstraintDistinctHosts, ConstraintDistinctProperty:
			mErr = multierror.Append(mErr, fmt.Errorf(
				"invalid constraint %s: host volumes of the same name are always on distinct hosts", constraint.Operand))

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Set capacity_max >= capacity_min in the volume request
2. Leave capacity_max unset if only a fixed capacity is needed

Example fix

// before
minBytes = 107374182400; maxBytes = 1073741824
// after
minBytes = 1073741824; maxBytes = 107374182400

if hv.RequestedCapacityMaxBytes < hv.RequestedCapacityMinBytes {
  return fmt.Errorf("capacity_max %d < capacity_min %d", hv.RequestedCapacityMaxBytes, hv.RequestedCapacityMinBytes)
}

if err := hv.Validate(); err != nil {
  return fmt.Errorf("check capacity_min/max ordering: %w", err)
}

When it happens

Trigger: Setting capacity_max below capacity_min in a host volume's requested capacity range, then validating/registering the volume.

Common situations: Swapped arguments when constructing the struct programmatically, unit mistakes (GB vs bytes) making the 'max' numerically smaller, or template variables resolved in the wrong order.

Related errors

• validating volume %q against state failed: %v
• volume validation failed: %w
• volume validation failed: no such namespace %q
• node ID %q is not in pool %q
• invalid ID %q

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/7e28921c63e29697. Report an issue: GitHub.