摘要 |
A common control redundancy switch method capable of, when an error occurs at an active common control unit, replacing the card at which the error occurs by a spare card, thereby performing operations as usual without affecting the overall network and, thus, reducing the time taken for repair during the stop of the system caused by the error. When a local control task of an active common control unit receives a switch message from a network management system via a configuration control task, it discriminates whether an inactive common control unit is at a switchover enable state. Upon receiving the switch message, an inactive common control unit transmits a response message to the switch message to a local control task of the active common control unit. When the local control task of the active common control unit receives the response message, a performance monitor gives a hardware initiated alarm informing of the initiation of the switchover routine. Where the inactive common control unit 20 is switched from the inactive state into the active state, it generates an activity switch result message informing of the switchover and sends it to the network management system. |