crowdsecurity/crowdsec · error

while starting flushMetrics scheduler: %w

Error message

while starting flushMetrics scheduler: %w

What it means

StartFlushScheduler registers a gocron job that runs flushMetrics every minute, deleting metrics older than metrics_max_age. This error wraps a scheduler.NewJob registration failure and aborts startup.

Source

Thrown at pkg/database/flush.go:131

		}
	}

	_, err = scheduler.NewJob(
		gocron.DurationJob(flushInterval),
		gocron.NewTask(c.FlushAgentsAndBouncers, ctx, config.AgentsGC, config.BouncersGC),
		gocron.WithSingletonMode(gocron.LimitModeReschedule),
	)
	if err != nil {
		return nil, fmt.Errorf("while starting FlushAgentsAndBouncers scheduler: %w", err)
	}

	_, err = scheduler.NewJob(
		gocron.DurationJob(flushInterval),
		gocron.NewTask(c.flushMetrics, ctx, time.Duration(config.MetricsMaxAge)),
		gocron.WithSingletonMode(gocron.LimitModeReschedule),
	)
	if err != nil {
		return nil, fmt.Errorf("while starting flushMetrics scheduler: %w", err)
	}

	_, err = scheduler.NewJob(
		gocron.DurationJob(flushInterval),
		gocron.NewTask(c.flushAllowlists, ctx),
		gocron.WithSingletonMode(gocron.LimitModeReschedule),
	)
	if err != nil {
		return nil, fmt.Errorf("while starting FlushAllowlists scheduler: %w", err)
	}

	scheduler.Start()

	return scheduler, nil
}

// flushMetrics deletes metrics older than maxAge, regardless if they have been pushed to CAPI or not
func (c *Client) flushMetrics(ctx context.Context, maxAge time.Duration) {

View on GitHub (pinned to 909b515798)

Solutions

1. Ensure the Client is non-nil and fully initialized.
2. Inspect the wrapped error for the gocron-level cause and correct that input.
3. Confirm earlier jobs in StartFlushScheduler did not leave the scheduler in a bad state.
4. Check config.MetricsMaxAge resolves to a sane (non-negative) duration.

Example fix

// before
scheduler, err := c.StartFlushScheduler(ctx, nil)

// after
if flushCfg == nil {
    flushCfg = csconfig.DefaultFlushDBCfg()
}
scheduler, err := c.StartFlushScheduler(ctx, flushCfg)

if config != nil && config.MetricsMaxAge < 0 {
    return errors.New("metrics_max_age must not be negative")
}

if c == nil || c.Ent == nil {
    return errors.New("database client not initialized")
}

scheduler, err := c.StartFlushScheduler(ctx, flushCfg)
if err != nil {
    if strings.Contains(err.Error(), "flushMetrics scheduler") {
        // scheduler registration failed
    }
    return err
}

When it happens

Trigger: scheduler.NewJob fails when registering the flushMetrics task — invalid task construction, scheduler in an invalid state, or gocron rejecting the job definition.

Common situations: Nil database Client making the method value unusable; time.Duration(config.MetricsMaxAge) computed from a config typo in a custom build; gocron option misuse.

Related errors

• while starting FlushAlerts scheduler: %w
• while starting FlushAgentsAndBouncers scheduler: %w
• while starting FlushAllowlists scheduler: %w
• empty cti key
• no listen_uri or listen_socket specified

AI-assisted analysis of crowdsecurity/crowdsec@909b515798 (2026-09-06). Data as JSON: /api/errors/567b8d939c8fc0bd. Report an issue: GitHub.