摘要 |
When a client sends an RPC request that requests a server for a service, the client adds identification information to the RPC request. When an active server receives an RPC request, it stores the identification information thereof in a stable area that is not destroyed even if a defect takes place in the client or the server, and executes the requested service. When a defect takes place in the active server, the backup server takes over the process of the active server. A PALIB of the backup server compares the identification information of the RPC request re-sent from the client with the identification information in the stable area. When they match, the PALIB determines that the RPC request is redundant. The backup server performs a redundant process and sends back the correct result to the client. |