Google Professional Cloud Network Engineer Question 217
Select 3Google Cloud PlatformYou are tasked with configuring VPC Network Peering between two VPC networks, 'VPC-A' and 'VPC-B,' in Google Cloud. After configuring the peering, you notice that some instances in 'VPC-B' cannot communicate with instances in 'VPC-A.' Which of the following steps should you take to resolve this issue?
- A
Ensure that both VPCs have routes pointing to the peered network.
- B
Verify that the firewall rules in both VPCs allow traffic between the instances.
- C
Enable DNS resolution for the peering connection.
- D
Check if subnets in both VPCs have overlapping IP ranges.
- E
Recreate the VPC peering to fix potential configuration issues.
Show answer and explanation
Correct answers: A, B, D
Explanation
When configuring VPC Network Peering, it is essential to ensure that routes and firewall rules are correctly configured in both VPCs to allow traffic between the networks. Additionally, IP ranges must not overlap, as overlapping ranges can cause routing conflicts. DNS resolution is optional and not required for basic communication. Recreating the peering is unnecessary unless all other troubleshooting steps fail.
- A. Correct.
Ensuring that both VPCs have the necessary routes is critical because VPC Network Peering does not automatically create routes for custom subnets. Missing routes can prevent traffic from flowing between the peered VPCs.
- B. Correct.
Firewall rules must explicitly allow traffic between instances in the peered networks. Without the correct rules, communication between instances in the two VPCs may be blocked.
- C. Incorrect.
Enabling DNS resolution is not required for basic communication between instances. It is only necessary if you want to resolve private DNS names across peered VPCs.
- D. Correct.
Overlapping IP ranges between the two VPCs will cause conflicts, preventing communication between instances. You must ensure that the IP ranges of the two VPCs do not overlap.
- E. Incorrect.
Recreating the VPC peering is rarely necessary and should only be considered after thoroughly investigating other potential issues such as routes, firewall rules, or IP range conflicts.