def add_fence_level(session, level, devices, node, remove = false)
  if not remove
    stdout, stderr, retval = run_cmd(
      session, PCS, "stonith", "level", "add", level, node, devices
    )
    return retval,stdout, stderr
  else
    stdout, stderr, retval = run_cmd(
      session, PCS, "stonith", "level", "remove", level, node, devices
    )
    return retval,stdout, stderr
  end
end
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.