Alibaba Cloud Certified Associate – Cloud Computing — Question 45

When using Alibaba Cloud SLB, you can set different weights for backend ECS instances. The higher the weight of a backend ECS instance, the more load will be assigned to it. If an SLB instance has 5 ECS instances in the backend server pool, all of which are healthy. Among these 5 ECS instances, the weight of ecs_inst1 is set to 100. Which of the following statements is correct?

Answer options

• A. We do not know the weight settings of the remaining 4 ECS instances, so we cannot tell what would happen.
• B. 100% of loads will be assigned to ecs_inst1, and the rest 4 ECS instances will stay idle.
• C. Based on SLB's working mechanism, approximately 20% of loads will be assigned to ecs_inst1.
• D. Based on request level parameters of external requests, all requests with a request level parameter of 100 will be transferred to ecs_inst1.

Correct answer: C

Explanation

The correct answer is C because SLB distributes load based on the weights assigned to each instance in relation to the total weights. Since we only know the weight of ecs_inst1, it cannot take all the load, and the other instances must be considered. Answers A, B, and D are incorrect as they either lack sufficient information or misinterpret how SLB distributes requests based on weights.