Google Professional Cloud Network Engineer Question 733
Single answerGoogle Cloud PlatformYour organization is using a Google Cloud HTTP(S) Load Balancer to manage traffic for a web application. The application is being upgraded, and you need to redirect all incoming traffic from the current backend service to a new backend service while ensuring that existing active connections are allowed to finish processing. How can you achieve this using the Load Balancer?
- A
Configure a URL map to redirect all traffic to the new backend service.
- B
Remove the current backend service from the load balancer and add the new backend service immediately.
- C
Set the current backend service to 'draining mode' and then add the new backend service to the load balancer.
- D
Update the backend service timeout policy to zero and switch traffic to the new backend service.
Show answer and explanation
Correct answer: C
Explanation
To redirect traffic while maintaining existing active connections, the proper method is to set the backend service to 'draining mode.' This allows ongoing connections to complete while new traffic is redirected to the new backend service. This process ensures minimal disruption to users and complies with best practices for traffic management using Google Cloud's HTTP(S) Load Balancer.
- A. Incorrect.
This option does not ensure existing active connections are preserved. URL maps are used for routing traffic based on URL patterns, not for connection draining.
- B. Incorrect.
Removing the current backend service immediately disrupts any active connections. This approach does not ensure a smooth transition.
- C. Correct.
Setting the current backend service to 'draining mode' ensures that existing active connections are allowed to finish processing while new connections are directed to the new backend service. This is the correct approach for traffic redirection during an upgrade.
- D. Incorrect.
Updating the backend service timeout policy to zero will abruptly terminate active connections, which is not suitable for preserving user experience during a migration.