HIGHLY AVAILABLE SYSTEM, SERVER, METHOD FOR MAINTAINING HIGH AVAILABILITY, AND PROGRAM

PROBLEM TO BE SOLVED: To maintain high availability while securing data consistency. SOLUTION: A highly available system continuously provides a predetermined service by one of servers belonging to each of a plurality of server groups mutually connected. A plurality of servers, belonging to each of the plurality of server groups, configures a first server group constituted of mutually communicable servers among the plurality of servers belonging to the server group concerned. When the number of servers in the first server group is larger than or equal to a predetermined number according to the number of servers in the server group, the server in the first server group selects representative servers of the server group from the servers in the first server group. A plurality of representative servers selected for each of the plurality of server groups selects a top representative server providing a predetermined service from the plurality of representative servers. COPYRIGHT: (C)2011,JPO&INPIT