Google Professional Cloud Network Engineer Question 752
Select 3Google Cloud PlatformYou manage a Google Cloud environment where an application running in a private VPC subnet cannot reach an external API hosted on the internet. You have already verified that the route to the internet via a Cloud NAT exists, but the issue persists. Which of the following steps can help you identify the root cause of the connectivity issue?
- A
Check the VPC Flow Logs to verify whether the traffic is reaching the NAT gateway.
- B
Analyze Packet Mirroring data to inspect the contents of the traffic leaving the VM.
- C
Review the firewall logs to ensure that the egress traffic is not being blocked by a firewall rule.
- D
Verify the IAM permissions for the service account attached to the VM.
- E
Check the Cloud NAT configuration to ensure the NAT IP range matches the destination IP range.
Show answer and explanation
Correct answers: A, B, C
Explanation
To troubleshoot connectivity issues effectively, it is critical to use the appropriate tools provided by Google Cloud. VPC Flow Logs, Packet Mirroring, and firewall logs each provide valuable insights into different aspects of network traffic, including routing, protocol behavior, and rule enforcement. By combining these tools, you can systematically identify and resolve the root cause of connectivity issues.
- A. Correct.
VPC Flow Logs can provide insights into whether traffic from the VM is reaching the NAT gateway, helping to identify potential routing or connectivity issues.
- B. Correct.
Packet Mirroring allows you to inspect traffic at the packet level, which can be helpful to understand if there are issues with the application data or protocol mismatches.
- C. Correct.
Firewall logs are essential to verify whether the traffic is being blocked by an egress or ingress firewall rule, which could prevent connectivity to the external API.
- D. Incorrect.
IAM permissions are unrelated to connectivity in this scenario, as the issue pertains to network traffic rather than access control policies.
- E. Incorrect.
The NAT IP range does not need to match the destination IP range. NAT configuration issues would typically involve incorrect association with subnets or improperly scoped routes.