Google Professional Cloud Network Engineer Question 750
Select 4Google Cloud PlatformYour organization reports that traffic between two virtual machines (VMs) in different VPCs connected via VPC Network Peering is failing. You suspect that a misconfigured firewall rule or a routing issue is causing the problem. Which steps should you take to troubleshoot this issue effectively using Google Cloud’s networking tools?
- A
Enable and review VPC Flow Logs for both VPCs to analyze rejected or dropped traffic.
- B
Use Packet Mirroring to capture packets between the two VMs to check for dropped packets or protocol-level issues.
- C
Review the firewall logs to identify any rules blocking the traffic between the two VMs.
- D
Delete and recreate the VPC Network Peering to ensure connectivity is re-established.
- E
Verify the route tables in both VPCs to ensure appropriate routes exist for the traffic between the VMs.
Show answer and explanation
Correct answers: A, B, C, E
Explanation
To troubleshoot connectivity issues between two VMs in different VPCs connected via VPC Network Peering, you should analyze VPC Flow Logs to identify rejected or dropped traffic, use Packet Mirroring for packet-level analysis, review firewall logs for potential rule misconfigurations, and verify route tables to ensure proper routing. Deleting and recreating the VPC Network Peering is not a standard troubleshooting step unless the problem is definitively identified as a peering issue.
- A. Correct.
VPC Flow Logs are a powerful tool for traffic analysis and can help identify rejected or dropped traffic. This is a crucial step in determining the issue.
- B. Correct.
Packet Mirroring allows you to capture and analyze network packets at a protocol level, which can help identify dropped packets or misconfigurations.
- C. Correct.
Firewall logs provide detailed information about the traffic being allowed or denied by the firewall rules. Reviewing these logs can help identify misconfigured rules.
- D. Incorrect.
Deleting and recreating the VPC Network Peering is not a proper troubleshooting step unless you confirm that the peering itself is misconfigured or not functioning properly. This option is not recommended as a first step.
- E. Correct.
Route tables determine how traffic is directed between VPCs. Verifying the routes is an essential part of troubleshooting inter-VPC connectivity issues.