ENARSI Exam - Question 100

Question

Refer to the exhibits. Which configuration allows spoke-to-spoke communication using loopback as a tunnel source?

Examice · Accepted Answer

For spoke-to-spoke communication using a loopback as a tunnel source in a Dynamic Multipoint Virtual Private Network (DMVPN), it is important that the configuration allows for dynamic discovery of the peers. The command 'crypto isakmp key cisco address 0.0.0.0' on the spokes would enable this dynamic peer discovery, as it allows the spoke devices to establish ISAKMP (Internet Security Association and Key Management Protocol) sessions with any peer, which is essential for dynamic spoke-to-spoke interactions. This configuration is necessary to facilitate the dynamic nature of the connections in a DMVPN setup and to ensure that the loopback addresses used for the tunnel sources can communicate properly.

studybuddy10 · Answer

Given answer is correct -  D , the spokes dynamic tunnels with loopback sources are coming from 2.2.2.2 and 3.3.3.3 so only spokes with 0.0.0.0 would satisfy that.

Bruffas · Answer

I would assume that since we see the config on one spoke, that alternative A already is set on the HUB.
In that case D is the only answer that makes sense.

HungarianDish_111 · Answer

for spoke-to-spoke we need to add this on the spokes too
https://community.cisco.com/t5/vpn/isakmp-with-0-0-0-0-dmvpn/td-p/4312380

chris7890 · Answer

Is it possible that the command must be executed on the hub and on the spoke router?

Configure ISAKMP on all devices:

...

crypto isakmp key cisco address 0.0.0.0

https://ccieme.wordpress.com/2021/09/09/cisco-dynamic-multipoint-vpn/

FrankZane · Answer

I think A is correct 
https://www.cisco.com/en/US/technologies/tk583/tk372/technologies_white_paper0900aecd802b8f3c.html

[Removed] · Answer

D is correct

tubirubs · Answer

lol. In ENARSI Certification Official Book BY CISCO, not explain to configure IKEv1, ONLY IKEv2. Cisco Tell that IKEv1 is not considerated, because IKEv2 have more features for protection, for example, DPD and cookie challenger and max-sa....

ENARSI Exam - Question 100

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