hashicorp/nomad · error

telemetry in-memory collection interval must be greater than

Error message

telemetry in-memory collection interval must be greater than zero

What it means

Telemetry in-memory metrics require a strictly positive collection interval: how often the agent samples metrics into the in-memory ring buffer. Validate() rejects values <= 0 because a non-positive interval would mean metrics are never collected (or division-by-zero style scheduling errors downstream).

Source

Thrown at command/agent/config.go:1525

			blocked = append(blocked, rule[1:])
		default:
			return nil, nil, fmt.Errorf("Filter rule must begin with either '+' or '-': %q", rule)
		}
	}
	return allowed, blocked, nil
}

// Validate the telemetry configuration options. These are used by the agent,
// regardless of mode, so can live here rather than a structs package. It is
// safe to call, without checking whether the config object is nil first.
func (t *Telemetry) Validate() error {
	if t == nil {
		return nil
	}

	// Ensure we have durations that are greater than zero.
	if t.inMemoryCollectionInterval <= 0 {
		return errors.New("telemetry in-memory collection interval must be greater than zero")
	}
	if t.inMemoryRetentionPeriod <= 0 {
		return errors.New("telemetry in-memory retention period must be greater than zero")
	}

	// Ensure the in-memory durations do not conflict.
	if t.inMemoryCollectionInterval > t.inMemoryRetentionPeriod {
		return errors.New("telemetry in-memory collection interval cannot be greater than retention period")
	}

	return nil
}

// Eventlog is the configuration for the Windows Eventlog
type Eventlog struct {
	// Enabled controls if Nomad agent logs are sent to the
	// Windows eventlog.
	Enabled bool `hcl:"enabled"`

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Set a positive collection interval (e.g. `metrics_interval = "10s"`) in the telemetry block.
2. If you want collection disabled, disable the in-memory metrics feature itself rather than setting interval 0.
3. Check where the interval value originates (flags/env/templates) and guard against zero there.

Example fix

// before
telemetry {
  in_memory_collection_interval = 0
}

// after
telemetry {
  in_memory_collection_interval = "10s"
}

if t := cfg.Telemetry; t != nil && t.InMemoryCollectionInterval <= 0 {
    return errors.New("telemetry collection interval must be > 0")
}

func positiveInterval(d time.Duration) bool { return d > 0 }

When it happens

Trigger: Agent telemetry config enables in-memory metrics and sets the internal inMemoryCollectionInterval (derived from e.g. `metrics_interval` or in-memory specific settings) to 0 or a negative duration, then calls the telemetry Validate().

Common situations: Setting interval to 0 to try to disable collection while leaving in-memory metrics enabled; automation computing the interval to zero; unit mixups producing a near-zero parsed duration.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

• telemetry in-memory retention period must be greater than ze
• telemetry in-memory collection interval cannot be greater th
• rpc.dial_timeout must be greater than or equal to zero
• hg_timeout must be > 0
• s3_timeout must be > 0

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/0dd3194767533ca6. Report an issue: GitHub.