Google Professional Cloud Network Engineer Exam - Topic 3 Question 114 Discussion

Actual exam question for Google's Professional Cloud Network Engineer exam

Question #: 114
Topic #: 3

[All Professional Cloud Network Engineer Questions]

Your on-premises data center has 2 routers connected to your Google Cloud environment through a VPN on each router. All applications are working correctly; however, all of the traffic is passing across a single VPN instead of being load-balanced across the 2 connections as desired.

During troubleshooting you find:

* Each on-premises router is configured with a unique ASN.

* Each on-premises router is configured with the same routes and priorities.

* Both on-premises routers are configured with a VPN connected to a single Cloud Router.

* BGP sessions are established between both on-premises routers and the Cloud Router.

* Only 1 of the on-premises router's routes are being added to the routing table.

What is the most likely cause of this problem?

AThe on-premises routers are configured with the same routes.

BA firewall is blocking the traffic across the second VPN connection.

CYou do not have a load balancer to load-balance the network traffic.

DThe ASNs being used on the on-premises routers are different.

Show Suggested Answer

Suggested Answer: D

https://cloud.google.com/network-connectivity/docs/router/support/troubleshooting#ecmp

by Johna at Nov 21, 2025, 12:09 AM

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Jules

2 days ago

I lean towards D. Unique ASNs should help with load balancing.

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Eveline

7 days ago

C makes sense. Without a load balancer, traffic won't split.

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Patrick

12 days ago

I feel like B is unlikely. Firewalls usually don't block VPNs like that.

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Franchesca

17 days ago

A is also possible. Same routes could lead to one being prioritized.

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Lili

23 days ago

I think it's C. No load balancer means no distribution.

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Willow

28 days ago

I disagree, the firewall could be the culprit here.

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Agustin

2 months ago

A load balancer isn't needed for VPN connections, right?

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Gaston

2 months ago

Surprised that the routes aren't being added from both routers!

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Gerald

2 months ago

I think it's definitely a routing problem.

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Tonette

2 months ago

Both routers have unique ASNs, so that's not the issue.

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Jackie

2 months ago

B) A firewall is blocking the traffic across the second VPN connection. Seems like the obvious choice to me.

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Bettyann

2 months ago

I bet the person who wrote this question has a secret passion for dad jokes.

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Myrtie

3 months ago

D) The ASNs being used on the on-premises routers are different.

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Shad

3 months ago

I thought load balancing was only necessary for certain setups, but since both routers are connected to the same Cloud Router, I wonder if that's the key issue here.

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Novella

3 months ago

I feel like the firewall option could be a red herring. If BGP is set up correctly, it should handle the routes, right?

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Janine

3 months ago

This seems like a classic BGP routing issue. The fact that only one router's routes are being added to the routing table suggests a problem with the BGP configuration or peering. I'd double-check the BGP settings and make sure the peering is set up correctly.

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Chaya

3 months ago

I think the question is trying to get us to think about the BGP routing process and how it handles multiple paths. If the routes and priorities are the same, then the ASNs being different should cause the routes to be load-balanced, not just use one. I'm going to go with option D.

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Son

3 months ago

I'm a bit confused by this one. The question mentions that the routes and priorities are the same on both routers, so I'm not sure why the ASNs being different would be the issue. Maybe there's something else going on with the BGP configuration?

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Belen

4 months ago

This seems similar to a practice question we did on VPN configurations. I think having the same routes might be a problem, but I can't recall the specifics.

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Karl

4 months ago

I remember something about BGP and how it handles multiple routes, but I'm not sure if the ASNs being different is the main issue here.

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Clorinda

4 months ago

Ah, the old "different ASNs" trick. Gotta love those networking conundrums!

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Serita

4 months ago

I agree, but D could be an issue too. Different ASNs might confuse routing.

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Gracie

5 months ago

Okay, let's see. The key details seem to be the unique ASNs on the routers and the fact that only one router's routes are being added. I'm leaning towards option D as the most likely cause.

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Karon

5 months ago

Hmm, this seems like a tricky one. I'll need to carefully review the details provided and think through the possible causes.

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Mauricio

4 months ago

I think it might be the ASNs being different.

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