L3 redundancy.pdf - the Netgroup at Politecnico di Torino

HSRP header: “opcode” field• Describes the type of message contained in this packet• Possible values• 0 = Hello• The router is running and is capable of becoming the active orstandby router• 1 = Coup• The router wants to become the active router• 2 = Resign• The router does no longer want to be the active router• “Coup” and “Resign” are not necessarily used together• E.g. a router that has highest priority can send the “coup” message totake over the current router, but this router goes into “speak” statewithout sending any “resign”15