| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve efficiency of recovery processing when failure occurs. <P>SOLUTION: Each slave node comprises: a request notification transmission unit 11 for transmitting a change request notification to become a new master node to other slave nodes on detecting failure in a master node; a permission notification transmission unit 12 which acquires the latest transaction numbers from the master node and the other slave nodes on receiving the change request notification, and when the transaction number of the master node is smaller than the transaction number of a transmission source of the change request notification, or when the transaction number of the master node could not be acquired, transmits a change permission notification to the transmission source of the change request notification; and a difference transmission unit 13 which executes change processing to become the new master node on receiving the change permission notification and transmits difference data to the old master node. The master node comprises a difference updating unit 14 which executes change processing to become a slave node on receiving the difference data, and updates data by the difference data. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
