private void validateBootstrapSessionManagerIsRunningOrThrow() {
    if (!isRunning) {
      logger.error("BootstrapSessionManager is not running.");
      throw new IllegalStateException("BootstrapSessionManager is not running.");
    }
  }
Checks if the BootstrapSessionManager is running.
@return true if the manager is running, false otherwise.
ambry-store/src/main/java/com/github/ambry/store/BootstrapSessionManager.java