vitessio/vitess · error

failed to configure stdin: %v

Error message

failed to configure stdin: %v

What it means

ExecuteAsWritePipe sets up the hook process's stdin as a pipe so the caller can write data to it. If cmd.StdinPipe() fails, the function aborts with HOOK_GENERIC_ERROR and this message. This is an OS-level pipe creation failure, occurring before the process starts.

Source

Thrown at go/vt/hook/hook.go:232

}

// ExecuteAsWritePipe will execute the hook as in a Unix pipe,
// directing output to the provided writer. It will return:
// - an io.WriteCloser to write data to.
// - a WaitFunc method to call to wait for the process to exit,
// that returns stderr and the cmd.Wait() error.
// - an error code and an error if anything fails.
func (hook *Hook) ExecuteAsWritePipe(out io.Writer) (io.WriteCloser, WaitFunc, int, error) {
	// Find the hook.
	cmd, status, err := hook.findHook(context.Background())
	if err != nil {
		return nil, nil, status, err
	}

	// Configure the process's stdin, stdout, and stderr.
	in, err := cmd.StdinPipe()
	if err != nil {
		return nil, nil, HOOK_GENERIC_ERROR, fmt.Errorf("failed to configure stdin: %v", err)
	}
	cmd.Stdout = out
	var stderr strings.Builder
	cmd.Stderr = &stderr

	// Start the process.
	err = cmd.Start()
	if err != nil {
		status = HOOK_CANNOT_GET_EXIT_STATUS
		if cmd.ProcessState != nil {
			status = cmd.ProcessState.Sys().(syscall.WaitStatus).ExitStatus()
		}
		return nil, nil, status, err
	}

	// And return
	return in, func() (string, error) {
		err := cmd.Wait()

View on GitHub (pinned to 01a25a7d17)

Solutions

1. Check and raise the file descriptor limit (ulimit -n) for the process
2. Audit the calling process for leaked pipes/files not being closed and fix the leak
3. Inspect the wrapped %v error from StdinPipe for the exact OS error (e.g. EMFILE)

Example fix

// before: 'failed to configure stdin: too many open files'
// after: raise FD limit for the service
ulimit -n 65536  # or set LimitNOFILE=65536 in systemd unit

if err := isFDHeadroomOK(4); err != nil {
    return fmt.Errorf("not enough file descriptors for hook pipe: %v", err)
}

hr, w, status, err := h.ExecuteAsWritePipe(ctx, nil)
if status == hook.HOOK_GENERIC_ERROR && strings.Contains(err.Error(), "failed to configure stdin") {
    return fmt.Errorf("pipe setup failed (check ulimit -n): %v", err)
}

When it happens

Trigger: Calling hook.ExecuteAsWritePipe when the exec.Cmd StdinPipe call fails — practically always due to OS resource exhaustion (too many open file descriptors) or a closed/broken process setup.

Common situations: File descriptor leaks exhausting the process's ulimit -n; running in a constrained container with a low FD limit; long-running processes accumulating unclosed pipes.

Related errors

• failed to configure stdout: %v
• cannot get VTROOT: %v
• invalid hook name %q: %v
• missing hook %v
• cannot stat hook %v: %v

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/fd7068781643d6a2. Report an issue: GitHub.