listeners.addListener(listener, executor);
    }

    void awaitHealthy() {
      monitor.enterWhenUninterruptibly(awaitHealthGuard);
      try {
        checkHealthy();
      } finally {
        monitor.leave();
      }
    }

    void awaitHealthy(long timeout, TimeUnit unit) throws TimeoutException {
      monitor.enter();
      try {

package cmd

import (
	"context"
	"net/http"
	"strconv"
	"time"

	xhttp "github.com/minio/minio/internal/http"
	"github.com/minio/minio/internal/kms"
)

const unavailable = "offline"

func checkHealth(w http.ResponseWriter) ObjectLayer {
	objLayer := newObjectLayerFn()
	if objLayer == nil {
		w.Header().Set(xhttp.MinIOServerStatus, unavailable)
		writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
		return nil