Cisco 300-440 Exam - Topic 5 Question 5 Discussion

Actual exam question for Cisco's 300-440 exam

Question #: 5
Topic #: 5

Refer to the exhibits.

Refer to the exhibit. An engineer successfully brings up the site-to-site VPN tunnel between the remote office and the AWS virtual private gateway, and the site-to-site routing works correctly. However, the end-to-end ping between the office user PC and the AWS EC2 instance is not working. Which two actions diagnose the loss of connectivity? (Choose two.)

ACheck the network security group rules on the host VNET.

BCheck the security group rules for the host VPC.

CCheck the IPsec SA counters.

DOn the Cisco VPN router, configure the IPsec SA to allow ping packets.

EOn the AWS private virtual gateway, configure the IPsec SA to allow ping packets.

Show Suggested Answer

Suggested Answer: B, C

The end-to-end ping between the office user PC and the AWS EC2 instance is not working because either the security group rules for the host VPC are blocking the ICMP traffic or the IPsec SA counters are showing errors or drops. To diagnose the loss of connectivity, the engineer should check both the security group rules and the IPsec SA counters. The network security group rules on the host VNET are not relevant because they apply to Azure, not AWS. The IPsec SA configuration on the Cisco VPN router and the AWS private virtual gateway are not likely to be the cause of the problem because the site-to-site VPN tunnel is already up and the site-to-site routing works correctly.Reference:=

Designing and Implementing Cloud Connectivity (ENCC, Track 1 of 5), Module 3: Configuring IPsec VPN from Cisco IOS XE to AWS, Lesson 3: Verify IPsec VPN Connectivity

Security for VPNs with IPsec Configuration Guide, Cisco IOS XE, Chapter: IPsec VPN Overview, Section: IPsec Security Association

AWS Documentation, User Guide for AWS VPN, Section: Security Groups for Your VPC

by Helene at Mar 10, 2024, 12:38 AM

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Melissa

4 months ago

Definitely check the network security group rules too!

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Jeannine

4 months ago

Wait, why would you need to configure the IPsec SA for ping? Seems odd.

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Elin

4 months ago

I think checking the IPsec SA counters is also important.

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Juliana

5 months ago

Totally agree, that’s a common issue!

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Virgina

5 months ago

Check the security group rules for the host VPC.

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Ronny

5 months ago

I think I read that allowing ping packets on the Cisco router is important, so D might be worth considering as well.

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Jaime

5 months ago

I feel like I should check both the network security group and the VPC security group rules, but I can't recall which one is more critical.

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Wendell

5 months ago

I'm a bit unsure, but I think checking the IPsec SA counters could help diagnose the issue too. Wasn't there a similar question about that?

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Denny

6 months ago

I remember something about checking security group rules being crucial for connectivity issues, so maybe B is a good choice.

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Gabriele

6 months ago

This seems like a tricky one. I'm not sure where the problem is exactly. I guess I'll start with the security group rules and go from there. Hopefully, I can figure it out.

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Jacqueline

6 months ago

Okay, I think I've got a good strategy here. I'll check the security group rules first, and if that doesn't work, I'll look into configuring the IPsec SA to allow ping packets on the Cisco VPN router or the AWS private virtual gateway.

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Solange

6 months ago

Hmm, I'm a bit confused. The VPN tunnel is working, so the issue must be somewhere else. Maybe I should check the IPsec SA counters to see if there are any errors or dropped packets.

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Ona

6 months ago

This question looks straightforward. I'll start by checking the security group rules on both the host VNET and the VPC to see if there are any issues with the allowed traffic.

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Ronald

6 months ago

Ah, I remember learning about Custom Alerts in class. I believe the correct answer is B, but I'll double-check the details.

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Na

6 months ago

Time management is crucial here. I'll quickly eliminate options that sound obviously correct and focus on finding the statement that seems off.

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Raul

6 months ago

I think all the options here sound like benefits, but isn't an audit mainly for internal control and not necessarily for streamlining? I'm a bit confused about that.

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Agustin

6 months ago

Okay, I think I know this one. A 3x6 FRA is a forward rate agreement, so the price would be based on the 3 month and 6 month interest rates, right?

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Reuben

6 months ago

I'm not entirely sure, but I think the Multimedia Contact Server alone might not be sufficient for some deployments. I need to think back on that one.

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Meaghan

2 years ago

I think we should configure the IPsec SA on the Cisco VPN router to allow ping packets.

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Delmy

2 years ago

We should also check the IPsec SA counters to see if there are any issues there.

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Yvonne

2 years ago

I agree with Elenor. We need to make sure the rules are not blocking the traffic.

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Elenor

2 years ago

I think we should check the network security group rules on the host VNET.

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Isaac

2 years ago

I think we should configure the IPsec SA on the Cisco VPN router to allow ping packets.

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Kirk

2 years ago

We should also check the IPsec SA counters to see if there are any issues there.

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Nathalie

2 years ago

I agree with Micheal. We need to make sure the rules are not blocking the traffic.

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Micheal

2 years ago

I think we should check the network security group rules on the host VNET.

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Felix

2 years ago

You guys are on the right track. But don't forget to check the AWS private virtual gateway as well. It could be an issue with the configuration there, not just the Cisco router. We need to cover all our bases.

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Maryann

2 years ago

Hmm, I'm leaning towards checking the security group rules first. That seems like the most logical step. I mean, the VPN tunnel is up, so the issue has to be somewhere in the network security.

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Youlanda

2 years ago

I agree, the security group rules are a good place to start. But we should also check the IPsec SA counters to see if there are any issues with the VPN tunnel itself. And we might need to configure the IPsec SA to allow ping packets on either the Cisco VPN router or the AWS private virtual gateway.

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Lawana

2 years ago

B) Check the security group rules for the host VPC.

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Lindy

2 years ago

Agreed, configuring the IPsec SA to allow ping packets on the gateway could help resolve the ping issue.

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Lemuel

2 years ago

E) On the AWS private virtual gateway, configure the IPsec SA to allow ping packets.

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Vernell

2 years ago

Yes, checking the IPsec SA counters is important to diagnose any tunnel issues.

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Sanjuana

2 years ago

D) On the Cisco VPN router, configure the IPsec SA to allow ping packets.

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Sue

2 years ago

C) Check the IPsec SA counters.

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Lai

2 years ago

A) Check the network security group rules on the host VNET.

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Lelia

2 years ago

This seems like a tricky question. The site-to-site VPN tunnel is working, but the end-to-end ping is not. I'm thinking we need to look at the security group rules on both the host VNET and the VPC. Might be an issue with the ICMP protocol not being allowed.

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