code: def __CleanUpCoresAlarm(self):
      
      instances = self.__GetAllInstances()
      clean_cores_cmd = """sudo sh -c 'rm /opt/cores/*'"""
      self.__RunCommandOnInstances(clean_cores_cmd, instances)
      return
docs: Disable core alarm.
      Mapr signals an alarm in the web ui when there are files in a nodes 
      /opt/cores dir.  This is anoying because we can't see if there is a real 
      problem with the node because of this pointless error message.  
      This removes those files so the alarm goes away.