@Override
  public synchronized void start() {
    if (started) {
      return;
    }
    authTokenSecretMgr = createSecretManager();
    if (authTokenSecretMgr != null) {
      // Start AuthenticationTokenSecretManager in synchronized way to avoid race conditions in
      // LeaderElector start. See HBASE-25875
      synchronized (authTokenSecretMgr) {
        setSecretManager(authTokenSecretMgr);
        authTokenSecretMgr.start();
      }
    }
    this.authManager = new ServiceAuthorizationManager();
    HBasePolicyProvider.init(conf, authManager);
    responder.start();
    listener.start();
    scheduler.start();
    started = true;
  }
Starts the service. Must be called before any calls will be handled.
hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleRpcServer.java