RELIEF METHOD FOR DUPLICATE SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an electronic switch or the like adopting a duplicate configuration where a BWB(back wiring board) is not separated between an active system and a standby system that permits replacement of the BWB without interrupting the service. SOLUTION: A relieve device 121 having the same printed circuit board and BWB as those of a faulty device 116 and a switch 131 are prepared in advance on the occurrence of a fault in a 0 system side of a BWB mounted with the faulty device 116, the functions of the faulty device 116 are transferred to the relief device 121 in the order of the 0 system and the 1 system so as to allow the relief device 121 to completely take over the services. For that time, the faulty device 116 is replaced with the switch 131 and the functions of the relief device 121 are transferred to the switch 131 in the order of the 0 system and the 1 system so as to allow the switch 131 to completely take over the services.