What causes "Interval must be a non zero value if Attempts > 0" in hashicorp/nomad?

Set reschedule.interval to a positive duration (e.g. interval = "30m").

Interval must be a non zero value if Attempts > 0

Error message

Interval must be a non zero value if Attempts > 0

What it means

ReschedulePolicy.Validate() in structs.go requires a non-zero Interval whenever Attempts > 0. A reschedule policy that limits attempts must define the window over which they are counted; Attempts > 0 with Interval <= 0 is ambiguous and rejected.

Source

Thrown at nomad/structs/structs.go:6655

func (r *ReschedulePolicy) Enabled() bool {
	enabled := r != nil && (r.Attempts > 0 || r.Unlimited)
	return enabled
}

// Validate uses different criteria to validate the reschedule policy
// Delay must be a minimum of 1 second
// Delay Ceiling is ignored if Delay Function is "constant"
// Number of possible attempts is validated, given the interval, delay and delay function
func (r *ReschedulePolicy) Validate() error {
	if !r.Enabled() {
		return nil
	}
	var mErr multierror.Error
	// Check for ambiguous/confusing settings
	if r.Attempts > 0 {
		if r.Interval <= 0 {
			_ = multierror.Append(&mErr, fmt.Errorf("Interval must be a non zero value if Attempts > 0"))
		}
		if r.Unlimited {
			_ = multierror.Append(&mErr, fmt.Errorf("Reschedule Policy with Attempts = %v, Interval = %v, "+
				"and Unlimited = %v is ambiguous", r.Attempts, r.Interval, r.Unlimited))
			_ = multierror.Append(&mErr, errors.New("If Attempts >0, Unlimited cannot also be set to true"))
		}
	}

	delayPreCheck := true
	// Delay should be bigger than the default
	if r.Delay.Nanoseconds() < ReschedulePolicyMinDelay.Nanoseconds() {
		_ = multierror.Append(&mErr, fmt.Errorf("Delay cannot be less than %v (got %v)", ReschedulePolicyMinDelay, r.Delay))
		delayPreCheck = false
	}

	// Must use a valid delay function
	if !isValidDelayFunction(r.DelayFunction) {
		_ = multierror.Append(&mErr, fmt.Errorf("Invalid delay function %q, must be one of %q", r.DelayFunction, RescheduleDelayFunctions))

View on GitHub (pinned to 482b49bf1a)

Solutions

Set reschedule.interval to a positive duration (e.g. interval = "30m").
If unlimited rescheduling is desired, set unlimited = true and attempts = 0 instead.
Run `nomad job validate` before submission to catch the missing field.

Example fix

// before
reschedule {
  attempts = 5
  delay    = "30s"
}
// after
reschedule {
  attempts = 5
  interval = "1h"
  delay    = "30s"
}

Defensive patterns

Strategy: validation

Validate before calling

if rsl := tg.Reschedule; rsl != nil && rsl.Attempts > 0 && rsl.Interval <= 0 {
    return fmt.Errorf("reschedule attempts=%d requires a positive interval", rsl.Attempts)
}

Type guard

func rescheduleSane(r *structs.ReschedulePolicy) bool {
    return r.Attempts == 0 || r.Interval > 0
}

Prevention

Never set attempts without also setting interval.
Use NewReschedulePolicy(jobType) defaults for limited policies.
Template generators should emit interval whenever attempts is emitted.

When it happens

Trigger: A reschedule block (or ReschedulePolicy struct built in code) with attempts set to a positive number but interval left at 0 or negative — often because interval was omitted from the job file or defaulted from the zero-value struct.

Common situations: Hand-written reschedule stanzas missing the interval line, JSON job payloads that omit the field, or constructors that set attempts without interval.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/6cf3ec06d9721354. Report an issue: GitHub.