Google Professional Cloud Network Engineer Question 220
Single answerGoogle Cloud PlatformYour organization manages two projects in Google Cloud: 'Project-A' and 'Project-B'. Both projects have a VPC network (VPC-A and VPC-B, respectively) that need to communicate with each other using private IP addresses. You are tasked with configuring VPC Network Peering between these two VPCs. After setting up the peering, you notice that instances in VPC-A can ping instances in VPC-B, but instances in VPC-B cannot reach instances in VPC-A. What is the most likely reason for this issue?
- A
The subnet IP ranges in VPC-A and VPC-B overlap, causing the peering connection to fail.
- B
You did not configure firewall rules to allow traffic between the two VPCs.
- C
The peering connection is pending acceptance in VPC-A.
- D
Routes for the peered VPCs were not automatically created in both networks.
Show answer and explanation
Correct answer: B
Explanation
When configuring VPC Network Peering, routes between the VPCs are automatically created, but firewall rules are not. You need to explicitly configure firewall rules to allow traffic between the VPCs. In this scenario, the lack of appropriate firewall rules is the most likely reason that instances in VPC-B cannot reach instances in VPC-A.
- A. Incorrect.
If the subnet IP ranges overlap, the peering connection would not have been established at all. This is not the cause of the issue described.
- B. Correct.
VPC Network Peering does not automatically configure firewall rules. You need to explicitly allow traffic between the VPCs using firewall rules. This is the correct answer.
- C. Incorrect.
VPC Network Peering does not require manual acceptance. Once configured on both sides, the peering connection is immediately active. This is not the cause of the issue.
- D. Incorrect.
Routes for the peered VPCs are automatically created when the peering connection is established. You do not need to configure them manually. This is not the cause of the issue.