Discuss Cisco 300-410 Exam Topic 11 Question 105

Refer to the exhibit.

R1 has a route map configured, which results in a loss of partial IPv6 prefixes for the BGP neighbor, resulting in service degradation. How can the full service be restored?

AThe neighbor requires a soft reconfiguration, and this will clear the policy without resetting the BGP TCP connection.

BThe prefix lit requires all prefixes that R1 is advertising to be added to it, and this will allow additional prefixes to be advertised.

CThe route map requires a deny 20 statement without set conditions, and this will allow additional prefixes to be advertised.

DThe route map requires a permit 20 statement without set conditions, and this will allow additional prefixes to be advertised.

Suggested Answer: A

In OSPF (Open Shortest Path First), the MTU (Maximum Transmission Unit) size must match on both sides of a link for OSPF neighbors to form an adjacency12.If the MTU sizes do not match, the OSPF adjacency will not form, and the routers will not become neighbors12.

In this case, R1 cannot establish a neighbor relationship with R2.One possible reason for this could be a mismatch in the MTU size on the interfaces of R1 and R212.

To resolve this issue, you can configure themtu ignorecommand on the interfaces of R1 and R2 (Option A).This command allows OSPF to ignore the MTU size when determining if it can form an adjacency with a neighbor12.This means that even if the MTU sizes do not match, OSPF will still form an adjacency, and R1 and R2 will become neighbors12.

OSPF MTU Mismatch - NetworkLessons.com

Understanding OSPF MTU Mismatch Conditions and Solutions - Cisco

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35 comments · newest first

Curtis 11 months ago

Soft reconfiguration is a solid choice too, but B might be better.

Glory 11 months ago

Option D seems too vague, not sure it would work.

Ivette 11 months ago

Wait, are we sure about option C? Sounds risky.

Precious 11 months ago

Definitely agree with that!

Vi 12 months ago

I think option B is the way to go.

Essie 12 months ago

The permit statement sounds familiar, but I’m uncertain if it’s the right one for restoring full service.

Annita 1 year ago

I feel like the deny statement could be the answer, but I can't recall the exact conditions we discussed in class.

Johana 1 year ago

I think we practiced a similar question where we had to adjust the route map. Maybe it's about adding prefixes to the list?

Marsha 1 year ago

I remember something about soft reconfiguration, but I'm not sure if that's the right approach here.

Iluminada 1 year ago

This is a tricky one, but I think the solution is in the route map. I'd start by looking at the "deny 20" statement and see if I can modify it to allow the missing prefixes to be advertised.

Eladia 1 year ago

Okay, let's think this through step-by-step. The key seems to be the route map configuration on R1. I'll need to analyze the route map and see if I can find a way to restore the full service.

Delsie 1 year ago

Hmm, I'm a bit unsure about this one. The question mentions a loss of partial IPv6 prefixes, so I'll need to carefully review the BGP neighbor configuration and the route map to see where the issue is.

Rhea 1 year ago

This looks like a classic BGP policy issue. I'd start by checking the route map configuration on R1 and see if I can identify the problem there.

Wava 1 year ago

Haha, this question is like a BGP Haiku - short, sweet, and full of hidden traps. Better choose wisely, folks!

Azzie 1 year ago

↳ replying to Wava

D) The route map requires a permit 20 statement without set conditions, and this will allow additional prefixes to be advertised.

Rodolfo 1 year ago

↳ replying to Wava

B) The prefix list requires all prefixes that R1 is advertising to be added to it, and this will allow additional prefixes to be advertised.

Timothy 1 year ago

↳ replying to Wava

A) The neighbor requires a soft reconfiguration, and this will clear the policy without resetting the BGP TCP connection.

Mabel 1 year ago

Wait, isn't option D just the opposite of what we want? Shouldn't we be restricting the route map, not allowing everything through?

Kimi 1 year ago

Hmm, the 'deny 20' option sounds a bit risky. I'd go with the 'permit 20' approach to open things up without any unintended consequences.

Jenifer 1 year ago

↳ replying to Kimi

Let's go with the 'permit 20' statement to restore the full service.

Rachael 1 year ago

↳ replying to Kimi

Agreed, the 'deny 20' option might cause more issues than it solves.

Roy 1 year ago

↳ replying to Kimi

I think so too, it's better to allow additional prefixes to be advertised.

Tony 1 year ago

↳ replying to Kimi

I agree, the 'permit 20' option seems like the safer choice.

Vilma 1 year ago

I'm not sure adding all prefixes to the prefix list is a good idea - that could potentially overload the router. The route map solution seems safer.

Edna 1 year ago

↳ replying to Vilma

User 3: The neighbor requires a soft reconfiguration to clear the policy without resetting the BGP TCP connection.

Lauran 1 year ago

↳ replying to Vilma

User 2: Agreed, adding all prefixes could overload the router.

Lottie 1 year ago

↳ replying to Vilma

User 1: I think the route map solution is safer.

Willodean 2 years ago

I'm not sure, but I think option A makes sense because it mentions clearing the policy without disrupting the connection.

Tanja 2 years ago

I agree with Elouise, a soft reconfiguration should clear the policy without resetting the BGP TCP connection.

Elouise 2 years ago

I think the answer is A) The neighbor requires a soft reconfiguration.

Carissa 2 years ago

The soft reconfiguration option seems like the quickest and cleanest way to restore full service without interrupting the BGP connection.

Bettina 1 year ago

↳ replying to Carissa

C) I think adding a deny statement to the route map without set conditions might also help.

Ashley 1 year ago

↳ replying to Carissa

A) That could work too, but the soft reconfiguration seems like the safer option.

Breana 1 year ago

↳ replying to Carissa

B) But wouldn't adding all prefixes that R1 is advertising to the prefix list also work?

Annice 2 years ago

↳ replying to Carissa

A) The neighbor requires a soft reconfiguration, and this will clear the policy without resetting the BGP TCP connection.

Cisco 300-410 Exam - Topic 11 Question 105 Discussion