// control, users can still opt-in to the previous behavior for closing the connections by
		// setting the environment variable DISABLE_HTTP2.
		if s := os.Getenv("DISABLE_HTTP2"); len(s) > 0 {
			klog.InfoS("HTTP2 has been explicitly disabled, Kubelet will forcefully close active connections on heartbeat failures")
			onHeartbeatFailure = closeAllConns
		} else {

// for the Proxy, Dial, and TLSHandshakeTimeout fields if unset
func SetTransportDefaults(t *http.Transport) *http.Transport {
	t = SetOldTransportDefaults(t)
	// Allow clients to disable http2 if needed.
	if s := os.Getenv("DISABLE_HTTP2"); len(s) > 0 {
		klog.Info("HTTP2 has been explicitly disabled")
	} else if allowsHTTP2(t) {
		if err := configureHTTP2Transport(t); err != nil {
			klog.Warningf("Transport failed http2 configuration: %v", err)
		}

  If users experiment problems with stale connections  using HTTP1.1, they can force the previous behavior of the kubelet by setting the environment variable DISABLE_HTTP2. ([#104844](https://github.com/kubernetes/kubernetes/pull/104844), [@aojea](https://github.com/aojea)) [SIG API Machinery, Auth and Node]

- The kubelet no longer forcefully closes active connections on heartbeat failures, using the HTTP2 health check mechanism to detect broken connections. Users can force the previous behavior of the kubelet by setting the environment variable DISABLE_HTTP2. ([#108107](https://github.com/kubernetes/kubernetes/pull/108107), [@aojea](https://github.com/aojea))