After how many NHRP registration request re-transmissions is a next-hop server (NHS) declared “down” if a spoke has not received an NHRP registration reply?
Explanation: NHRP registration requests are sent by the spoke every NHRP timeout period. If an NHRP registration reply is not received, the spoke will make three additional attempts. If after the third additional attempt a reply is not received, the NHS is declared “down”.
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