Network appliance redundancy system, control apparatus, network appliance redundancy method and program

Abstract

A network appliance redundancy system includes: a first switch arranged upstream of two different models of network appliances each of which switchably operates in an active system and a standby system; a second switch arranged downstream of the two different models of network appliances; and a control apparatus comprising a translation rule management unit learning a header translation rule(s) of a network appliance operating in the active system on the basis of header information of a packet transmitted from the first switch and header information of a packet received by the second switch via the network appliance operating in the active system and instructing, when the appliances in the active and standby systems are switched, the second switch to rewrite header information on the basis of the header translation rule(s) so as to obtain the same output packet as that from the network appliance operating in the active system.