hashicorp/nomad · error

failures_before_warning must be non-negative

Error message

failures_before_warning must be non-negative

What it means

validateConsul found a negative failures_before_warning value on a Consul check; warning/critical threshold counters must be non-negative integers.

Source

Thrown at nomad/structs/services.go:454

	// and Nomad when using the pass/fail check threshold features.
	//
	// Consul only.
	passFailCheckTypes := []string{"tcp", "http", "grpc"}

	if sc.SuccessBeforePassing < 0 {
		return fmt.Errorf("success_before_passing must be non-negative")
	} else if sc.SuccessBeforePassing > 0 && !slices.Contains(passFailCheckTypes, sc.Type) {
		return fmt.Errorf("success_before_passing not supported for check of type %q", sc.Type)
	}

	if sc.FailuresBeforeCritical < 0 {
		return fmt.Errorf("failures_before_critical must be non-negative")
	} else if sc.FailuresBeforeCritical > 0 && !slices.Contains(passFailCheckTypes, sc.Type) {
		return fmt.Errorf("failures_before_critical not supported for check of type %q", sc.Type)
	}

	if sc.FailuresBeforeWarning < 0 {
		return fmt.Errorf("failures_before_warning must be non-negative")
	} else if sc.FailuresBeforeWarning > 0 && !slices.Contains(passFailCheckTypes, sc.Type) {
		return fmt.Errorf("failures_before_warning not supported for check of type %q", sc.Type)
	}

	// Arbitrary value, we could bump it if needed
	if len(sc.Notes) > 255 {
		return fmt.Errorf("notes must not be longer than 255 characters")
	}

	return nil
}

// RequiresPort returns whether the service check requires the task has a port.
func (sc *ServiceCheck) RequiresPort() bool {
	switch sc.Type {
	case ServiceCheckGRPC, ServiceCheckHTTP, ServiceCheckTCP:
		return true
	default:

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Set failures_before_warning to 0 or a positive integer

Example fix

// before
check {
  failures_before_warning = -2
}
// after
check {
  failures_before_warning = 2
}

if sc.FailuresBeforeWarning < 0 {
    return fmt.Errorf("failures_before_warning must be non-negative")
}

func validFailuresBeforeWarning(sc *ServiceCheck) bool { return sc.FailuresBeforeWarning >= 0 }

When it happens

Trigger: Setting check.FailuresBeforeWarning to a negative integer in a Consul service check and validating it.

Common situations: Negative default from variable interpolation; mistyped value; copy-paste introducing a leading minus sign.

Related errors

• expose may only be set for Consul service checks
• on_update may only be set to ignore_warnings for Consul serv
• success_before_passing may only be set for Consul service ch
• failures_before_critical may only be set for Consul service
• failures_before_warning may only be set for Consul service c

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/fdddabaf7be08af5. Report an issue: GitHub.