Abstract: An information processing system, method, and apparatus reduces maintenance costs and management work and expedites countermeasures. A guide for a new event is selected based on information transmitted from the monitoring target node at which the new event has occurred; whether a countermeasure designated by the guide selected for the new event can be executed or not is judged; under this circumstance, past events having similarity to the new event which has occurred at the monitoring target node are identified; and if countermeasures against a specified last number of the past events among the identified past events have been successful and a countermeasure against the past event which is the latest and is more similar to the new event among the past events identified as the new event has been successful, it is judged that the countermeasure designated by the guide selected by the guide selection unit should be executed.