Google Professional Cloud Network Engineer Question 731
Select 3Google Cloud PlatformYou are managing a production application hosted on Google Cloud that uses an Application Load Balancer (ALB) to distribute traffic across multiple backend services. One of the backend services needs to be updated, and you want to ensure that existing connections to this backend are not disrupted while draining traffic. What steps should you take to achieve this?
- A
Set the backend service's 'Connection Draining Timeout' to a suitable value in the ALB configuration.
- B
Create a URL map to route all new traffic away from the backend service.
- C
Disable the backend service immediately to stop new traffic from reaching it.
- D
Use the 'Drain Connections' feature in the backend service to allow existing connections to complete.
- E
Manually terminate all active connections to the backend service.
Show answer and explanation
Correct answers: A, B, D
Explanation
To safely update a backend service without disrupting existing connections, you should configure connection draining to allow ongoing requests to complete, use a URL map to redirect new traffic, and leverage the 'Drain Connections' feature. Avoid abrupt actions such as disabling the backend or manually terminating connections, as they can cause disruptions for users.
- A. Correct.
This is correct. Configuring the 'Connection Draining Timeout' ensures ongoing requests are given time to complete before the backend is removed from service.
- B. Correct.
This is correct. Modifying the URL map to redirect new traffic ensures that the backend service no longer receives new requests while it is being drained.
- C. Incorrect.
This is incorrect. Disabling the backend service immediately would disrupt any ongoing connections, leading to potential downtime or failed requests.
- D. Correct.
This is correct. The 'Drain Connections' feature ensures that existing connections are allowed to gracefully complete before the backend service is taken out of rotation.
- E. Incorrect.
This is incorrect. Manually terminating connections would disrupt existing users and is not a recommended practice for handling traffic during maintenance.