Google Professional Cloud Network Engineer Question 767
Select 2Google Cloud PlatformYou have deployed a web application on a VM instance in Google Cloud. The VM is in a custom VPC network with a subnet configured for private IPs only. A load balancer is configured to serve traffic to the VM from the internet. Users report that they are unable to access the application. You suspect a route or firewall misconfiguration. Which steps should you take using Connectivity Tests to diagnose the issue?
- A
Create a Connectivity Test to simulate traffic from the internet to the VM's private IP.
- B
Create a Connectivity Test to simulate traffic from the load balancer to the VM's private IP.
- C
Check the Connectivity Test results for dropped steps due to a firewall rule denying traffic.
- D
Check the Connectivity Test results for dropped steps due to a missing route for internet-bound traffic.
- E
Use Connectivity Tests to directly modify the firewall rules and routes that are misconfigured.
Show answer and explanation
Correct answers: B, C
Explanation
To diagnose route and firewall misconfigurations using Connectivity Tests, you need to simulate the traffic flow that is failing. In this case, the traffic flows from the load balancer to the VM. By analyzing the Connectivity Test results, you can identify dropped steps due to firewall rules or other misconfigurations. Connectivity Tests provide detailed insights but do not modify configurations directly.
- A. Incorrect.
Creating a Connectivity Test to simulate traffic from the internet to the VM's private IP is invalid because the VM has private IPs only, and traffic from the internet would first reach the load balancer, not the VM directly.
- B. Correct.
Creating a Connectivity Test to simulate traffic from the load balancer to the VM's private IP is the correct approach because it reflects the actual path of traffic within the network.
- C. Correct.
Checking the Connectivity Test results for dropped steps due to a firewall rule denying traffic is a valid diagnostic step, as Connectivity Tests highlight misconfigured or missing firewall rules.
- D. Incorrect.
Connectivity Tests do not diagnose issues with internet-bound traffic in this scenario because the issue pertains to traffic between the load balancer and the VM, not outbound routes from the VM to the internet.
- E. Incorrect.
Connectivity Tests cannot directly modify firewall rules or routes; they are a diagnostic tool only, not a configuration tool.