ACP-Cloud1 Exam Dumps : ACP Cloud Computing Certification

ApsaraDB for RDS is a stable and reliable online database service that supports MySQL, SQL Server, PostgreSQL, MariaDB, and PPAS. ApsaraDB for RDS provides a read/write splitting feature that allows you to create read-only RDS instances, which can offload read requests from the primary RDS instance of your database system1. Read/write splitting is implemented by using a dedicated proxy endpoint, which routes read and write requests to different RDS instances based on the SQL statements and the read weights of the read-only instances2. By using ApsaraDB for RDS to implement read/write splitting, you can achieve the following benefits21:

Read requests are distributed to multiple instances. This can improve the read performance and availability of your database system, as well as balance the load among the read-only instances. You can specify the read weights of the read-only instances to control the distribution of read requests.

Read/write requests to the database are separated. This can reduce the pressure on the primary RDS instance and ensure the stability and security of the write operations. You only need to connect to the proxy endpoint, and the proxy will automatically route the read and write requests to the appropriate RDS instances.

The other statements are not correct, as write requests are not distributed to multiple instances, but only sent to the primary RDS instance2; and both read and write requests are not distributed to multiple instances, but separated by the proxy endpoint2. References: [ApsaraDB for RDS - Alibaba Cloud], Read/write splitting - - Alibaba Cloud Documentation Center, Use the read/write splitting feature to increase the processing capability of an ApsaraDB RDS instance

Alibaba Cloud Server Load Balancer (SLB) is designed to distribute incoming network traffic across multiple ECS instances within Alibaba Cloud, enhancing fault tolerance and application reliability. Backend servers for SLB must be Alibaba Cloud ECS instances, as SLB is specifically optimized to work within the Alibaba Cloud ecosystem. While it does not support instances from other cloud providers, it ensures integration and performance with Alibaba Cloud’s ECS instances.

According to the Alibaba Cloud documentation1, Auto Scaling is a service that automatically adjusts the number of elastic computing resources based on your business demands and policies. When the demand for computing resources increases, Auto Scaling automatically adds ECS instances to ensure sufficient computing capabilities. When the demand decreases, Auto Scaling automatically removes ECS instances to reduce costs.

Auto Scaling supports adding an existing ECS instance into the scaling group, but the instance must meet some requirements1. One of the requirements is that the instance and the scaling group must be in the same region. However, they do not have to be in the same zone. A zone is a physical area within a region that has independent power grids and networks. A region is a geographic area where Alibaba Cloud deploys its resources. Therefore, the correct answer is B.

References:

1: Auto Scaling: Automatically Adjusts Computing Resources - Alibaba Cloud

2: Introduction to Auto Scaling - Alibaba Cloud Document Center