grafana/k6 · error

start local execution

Error message

start local execution: %w

What it means

The StartLocalExecution call inside ProvisionLocalExecution failed — the request to begin a cloud-managed local-execution run (carrying Options, MaxVUs, TotalDuration, ArchiveSize) was rejected or did not complete. The wrapped error distinguishes HTTP rejection (ResponseError with status/body) from transport failure (network error).

Solutions

1. Check the wrapped error's HTTP status and body — fix the reported field (options vs MaxVUs vs duration)
2. Stop any still-running previous run of the same test in the Grafana Cloud UI or via `k6 cloud` commands, then retry
3. Verify quota/plan limits for concurrent runs, max VUs, and duration in your Grafana Cloud project
4. Re-authenticate with `k6 cloud login` if the status is 401/403

Example fix

// before
maxVUs := int64(1000) // hand-typed, may contradict script options
sleResp, err := client.StartLocalExecution(ctx, loadTestID, provisioning.StartLocalExecutionRequest{MaxVUs: maxVUs, ...})

// after
maxVUs := int64(et.GetMaxPossibleVUs()) // derived from the same execution plan
sleResp, err := client.StartLocalExecution(ctx, loadTestID, provisioning.StartLocalExecutionRequest{MaxVUs: maxVUs, ...})

// keep sizing consistent with the execution plan before calling
et, err := lib.NewExecutionTuple(seg, seq)
if err != nil { return err }
plan := cfg.Scenarios.GetFullExecutionRequirements(et)
maxVUs := int64(plan.GetMaxPossibleVUs())
total := int64(plan.GetDuration() / time.Second)

sleResp, err := c.StartLocalExecution(ctx, loadTestID, sleReq)
if err != nil {
    var respErr *cloudapiv6.ResponseError
    if errors.As(err, &respErr) {
        switch respErr.Response.StatusCode {
        case 409: return nil, fmt.Errorf("previous run still active: %w", err)
        case 402, 429: return nil, fmt.Errorf("quota exceeded: %w", err)
        }
    }
    return nil, fmt.Errorf("start local execution: %w", err)
}

When it happens

Trigger: 400 validation when MaxVUs or TotalDuration contradict the marshalled options, quota/plan limits exceeded (402/429), another run of the same test still active (409), invalid token (401), or network failure reaching the provisioning endpoint.

Common situations: Sizing parameters computed from a script whose scenarios changed between builds, free-tier limits on VUs or duration, a leftover running test from a crashed previous session, or a stale login configuration.

Understand the failure class

Background: "API request failed": what wrapped HTTP errors from external APIs mean and how to find the real cause — this error's family across 29 libraries.

Related errors

• create or find load test
• invalid stack URL
• max_vus
• notify test run completed
• stack URL is required to validate token

AI-assisted analysis of grafana/k6@01ffac6f24 (2026-08-18). Data as JSON: /api/errors/7b51a84ebca74921. Report an issue: GitHub.

Appendix: source

Thrown at internal/cloudapi/provisioning/provision.go:87

	if params.Archive != nil {
		var buf bytes.Buffer
		if err := params.Archive.Write(&buf); err != nil {
			return nil, fmt.Errorf("serialising archive: %w", err)
		}
		archiveSize = int64(buf.Len())
		archiveBytes = buf.Bytes()
	}

	sleReq := StartLocalExecutionRequest{
		Options:       params.Options,
		MaxVUs:        params.MaxVUs,
		TotalDuration: params.TotalDuration,
		ArchiveSize:   archiveSize,
	}

	sleResp, err := c.StartLocalExecution(ctx, loadTestID, sleReq)
	if err != nil {
		return nil, fmt.Errorf("start local execution: %w", err)
	}

	switch {
	case params.Archive != nil && sleResp.ArchiveUploadURL != nil:
		if err := c.UploadArchive(ctx, *sleResp.ArchiveUploadURL, archiveBytes); err != nil {
			return nil, fmt.Errorf("upload archive: %w", err)
		}
	case params.Archive != nil && sleResp.ArchiveUploadURL == nil:
		// We had an archive to upload but the API returned no upload URL;
		// proceed without uploading rather than failing the run.
		c.logger.Warn("archive present but provisioning API returned no upload URL; skipping archive upload")
	}

	if err := c.WaitForTestRunReady(ctx, sleResp.TestRunID, params.PollInterval); err != nil {
		return nil, fmt.Errorf("wait for test run ready: %w", err)
	}

	return &ProvisionResult{

View on GitHub (pinned to 01ffac6f24)