摘要 |
In a cluster that is composed of two computer nodes and has no common storage, mutual aliveness is monitored over networks. However, this is insufficient because a party node may be wrongly determined as inactive. If failover is performed according to wrong determination, the counterpart may be restored to a normal condition after the failover, so that both the two computers may operate as master. The two nodes to constitute the cluster and other computers to communicate with the cluster are connected by switches that can disable ports to which the computers are connected. A network control program that controls the switches changes the legality of use of ports to which the nodes are connected, synchronously with node failover. |