ACP-Cloud1 Exam Dumps : ACP Cloud Computing Certification

 To execute a task at a specific time such as removing 1 ECS instance every night at 00:00, you need to perform two operations: create a scaling rule and create a scheduled task. A scaling rule is a set of instructions that defines how Auto Scaling scales computing resources in response to changes in business load. A scheduled task is a type of scaling task that can execute a specified scaling rule at a specified time. By creating a scaling rule that removes 1 ECS instance from the scaling group, and creating a scheduled task that executes this scaling rule every night at 00:00, you can achieve the desired result. You do not need to create a new scaling group, because you already have one scaling group created. You also do not need to create an event-triggered task, because this type of scaling task is triggered by events such as Cloud Monitor alarms or API calls, not by a specific time. References: 1, 2, and 3.

Before data communication is set up, the security groups match the security group rules one by one to query whether to allow access requests. If the protocol type, port range, authorization type, and authorization object of two security group rules are the same, the following rules apply:

If the two rules have the same priority, the rule of the denial policy takes effect first, and the rule of the allowed policy does not take effect. This is because the security group rules follow the principle of minimum permission, which means that the most restrictive rule is applied when there is a conflict.

If the two rules have different priorities, the rule with a smaller priority number takes effect. This is because the security group rules follow the principle of priority, which means that the rule with a higher priority (lower number) is applied when there is a conflict. References: ECS Security Groups - Alibaba Fundamentals - Cloud Academy, Security group rules - Elastic Compute Service - Alibaba Cloud Documentation Center

For a service focused on storing and providing fast access to a massive amount of images, the team should use:

Object Storage Service (OSS): For scalable and cost-effective storage of large image datasets.

Elastic Compute Service (ECS): For running the application’s backend and API logic.

Content Delivery Network (CDN): To cache and accelerate image delivery globally, improving access speed for users worldwide.While Auto Scaling is useful for applications with highly variable compute demands, it is not essential for this setup based on the described requirements.