grafana/k6 · error

the Gateway Output failed to start a versioned output: %w

Error message

the Gateway Output failed to start a versioned output: %w

What it means

Start failed while switching to the versioned cloud output implementation: after creating the test run, startVersionedOutput returned an error (e.g. unsupported API version or v2 constructor failure) and Start wraps it with this message.

Source

Thrown at internal/output/cloud/output.go:293

		Archive:    out.testArchive,
	}

	response, err := out.client.CreateTestRun(testRun)
	if err != nil {
		return err
	}
	out.testRunID = response.ReferenceID

	if response.ConfigOverride != nil {
		out.logger.WithFields(logrus.Fields{
			"override": response.ConfigOverride,
		}).Debug("overriding config options")
		out.config = out.config.Apply(*response.ConfigOverride)
	}

	err = out.startVersionedOutput()
	if err != nil {
		return fmt.Errorf("the Gateway Output failed to start a versioned output: %w", err)
	}

	out.logger.WithFields(logrus.Fields{
		"name":      out.config.Name,
		"projectId": out.config.ProjectID,
		"duration":  out.duration,
		"testRunId": out.testRunID,
	}).Debug("Started!")
	return nil
}

// Description returns the URL with the test run results.
func (out *Output) Description() string {
	return fmt.Sprintf("cloud (%s)", cloudapi.URLForResults(out.testRunID, out.config))
}

// SetThresholds receives the thresholds before the output is Start()-ed.
func (out *Output) SetThresholds(scriptThresholds map[string]metrics.Thresholds) {

View on GitHub (pinned to 01ffac6f24)

Solutions

1. Inspect the wrapped error for the root cause (commonly an invalid K6_CLOUD_API_VERSION)
2. Set K6_CLOUD_API_VERSION=2
3. Verify cloud credentials, legacy/summary flags, and connectivity to the cloud API

When it happens

Trigger: Thrown at internal/output/cloud/output.go:293 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@01ffac6f24 (2026-08-18). Data as JSON: /api/errors/d4a9268fd603a07d. Report an issue: GitHub.