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JN0-664 Exam - Question 44


Click the Exhibit button.

Referring to the exhibit, which three statements are correct about route 10.0.0.0/16 when using the default BGP advertisement rules? (Choose three.)

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Correct Answer: ACE

Considering the default BGP advertisement rules: R1 will advertise the route 10.0.0.0/16 to R2 with 192.168.1.1 as the next hop, which aligns with basic IBGP behavior where the next hop does not change. R2 will then advertise the route 10.0.0.0/16 to R4 with 172.16.1.1 as the next hop, which is standard eBGP behavior where the next hop address is updated to the router itself. R4, when advertising this route to R6, will use the next hop of 172.16.1.2, not changing the next hop within the same AS. Therefore, A, C, and E are correct.

Discussion

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ce57f43Options: ACE
Mar 19, 2024

A,C, E is correct. Next Hop Self rule is for incoming routes, not when you are advertising.

141f14b
Jun 29, 2024

C - this answer is still tricky because next-hop-self is not a default behavior on IBGP. But with B,D clearly wrong this seems the way to go.

M80TOptions: ACE
Jan 17, 2024

B is incorrect, as an BGP router cannot send an IBGP route out to another IBGP peer (unless its configured as a route-reflector) D is incorrect as the AS Path attribute only gets prepended when advertising over EBGP peerings.

tsukasa123Options: ABC
Dec 8, 2023

Since R1 is connected to R2 and R3 with ibgp neighbor, next-hop is not changed and 192.168.1.1 is advertised. R2 is connected to R4 with ebgp neigibor, so 172.16.1.1 is advertised as the next-hop. R4 advertises nexthop 172.16.1.2 to R6.

a65ecbc
Dec 9, 2023

By default R2 does not advertise to R3 because it is learned by IBGP.

Bob_Smith
Jan 5, 2024

By default, a router does not re-advertise to an IBGP neighbor a route that itself has learned from IBGP

Bob_SmithOptions: ACE
Dec 31, 2023

A, C, E A- R2 will advertise 10.0.0.0/16 to R4 with 172.16.1.1 as next-hop...Standard eBGP behavior changing the next hop to self when redistributing iBGP routes to eBGP C - R1 will advertise 10.0.0.0/16 to R2 with 192.168.1.1 as next-hop. Basic iBGP behavior E - R4 will advertise 10.0.0.0/16 to R6 with 172.16.1.1 as next-hop. When advertising routes learned from eBGP to iBGP neighbors, the next-hop is not changed by default.

stewegOptions: ACE
Feb 14, 2024

I agree with M80T

marius2Options: ACE
Mar 4, 2024

ACE is correct.

antigel8Options: ACE
Mar 29, 2024

ACE is the correct answer

fukJUNIPEROptions: ACE
May 6, 2024

R2 will not send the route to R3