Alibaba Cloud ACA-Cloud1問題集で必ず試験合格させる [Q11-Q33]

Alibaba Cloud ACA-Cloud1問題集で必ず試験合格させる

ACA-Cloud1試験問題（更新されたのは2025年）100%リアル問題解答

質問 # 11
Auto Scaling can automatically remove unhealthy ECS instances from the scaling group (this feature is called Elastic Self-Health). Yet, after removal, the user has to manually add equivalent amount of new ECS instances back to the scaling group.

A. FALSE
B. TRUE

正解：A

解説：
Explanation
B is the correct answer because Auto Scaling can automatically remove unhealthy ECS instances from the scaling group, and also automatically add equivalent amount of new ECS instances back to the scaling group.
This feature is called Elastic Self-Health, and it can improve the availability and reliability of the scaling group. Elastic Self-Health can be enabled or disabled in the scaling group settings. When Elastic Self-Health is enabled, Auto Scaling monitors the health status of the ECS instances in the scaling group based on the health check results of the Server Load Balancer (SLB) instances that are associated with the scaling group. If an ECS instance is detected as unhealthy by SLB for a specified period of time, Auto Scaling removes the unhealthy ECS instance from the scaling group and releases it. Then, Auto Scaling triggers a scale-out event to add a new ECS instance to the scaling group to maintain the desired capacity12 References: 1: Elastic Self-Health 2: Enable or disable Elastic Self-Health

質問 # 12
Alibaba Cloud relational database service (RDS) is a stable, reliable and elastic online database service. RDS supports below database types? (Choose three.)

A. Oracle database
B. PostgreSQL
C. MySQL
D. SQL Server

正解：B、C、D

解説：
Explanation
Alibaba Cloud relational database service (RDS) is a stable, reliable and elastic online database service that supports various database engines, such as MySQL, SQL Server, PostgreSQL, MariaDB, and PPAS (PostgreSQL with Oracle compatibility)1. RDS provides high availability, backup and recovery, security, and monitoring features for your databases. RDS does not support Oracle database, which is a proprietary database system developed by Oracle Corporation2. If you need to use Oracle database on Alibaba Cloud, you can deploy it on an ECS instance or use the Oracle Database Backup Service3.
References: 1: Alibaba Cloud Academy, "RDS Concepts",
https://edu.alibabacloud.com/elearning/lesson/ACA-Cloud-Computing-Certification/lesson-5-rds-concepts 2:
Oracle, "Oracle Database", https://www.oracle.com/database/ 3: Alibaba Cloud, "Oracle Database Backup Service", https://www.alibabacloud.com/product/oracle-database-backup-service

質問 # 13
Alibaba Cloud does not support Intranet communication between products that are not in the same region, which does not mean ?

A. ECS instances and other products in different regions, such as ApsaraDB for RDS and OSS instances, cannot communicate with each other on the intranet.
B. ECS instances in different regions cannot communicate with each other on the intranet.
C. Server Load Balancer can be deployed for ECS instances in various regions.
D. Server Load Balancer cannot be deployed for ECS instances in various regions.

正解：A

解説：
Reference:
https://www.alibabacloud.com/help/doc-detail/40654.htm

質問 # 14
Your website has high volume of traffic and sudden spikes for a very short time. In this scenario, can manage traffic peak efficiently and maintain a consistent user experience.

A. Auto Scaling
B. Server Load Balancer
C. RDS
D. VPC

正解：A

解説：
Explanation
Auto Scaling is a service that automatically adjusts computing resources based on your volume of user requests. When the demand for computing resources increases, Auto Scaling automatically adds ECS instances to serve additional user requests, or alternatively removes instances in the case of decreased user requests1. Auto Scaling can help you manage traffic peaks efficiently and maintain a consistent user experience by scaling up or down your ECS instances according to your predefined policies and business needs2. References: 1: Auto Scaling: Automatically Adjusts Computing Resources - Alibaba Cloud2: Overview - Auto Scaling - Alibaba Cloud Documentation Center.

質問 # 15
Server Load Balancer supports protocols like. (Choose four.)

A. TCP
B. MQTT
C. HTTPS
D. HTTP
E. MPLS
F. UDP

正解：A、C、D、F

解説：
Explanation
Comprehensive protocol support - ICMP, TCP, UDP, HTTP, HTTPS,

質問 # 16
ECS can be used along with ______ to store static images, videos, and reducing storage fees.

A. Server Load Balancer
B. RDS
C. VPC
D. OSS

正解：D

解説：
Explanation/Reference: http://static-aliyun-doc.oss-cn-hangzhou.aliyuncs.com/download/pdf/DNA0011858383_en- US_intl_190320132947_public_91775d442a4b315acafcb25df8bcc84f.pdf

質問 # 17
www.company.com is a newly launched social portal for exchanging automotive information. The portal is based on PHP, including 10GB of images, and some JavaScripts files. Currently one single ECS instance is used to host all the application content as well as a MySQL database. With the growing number of users, the portal is getting slower to load images or respond to user requests. Moreover, there will be additional 50GB image content uploaded to the portal every week. Which combination of Alibaba Cloud services below can help resolve the storage and performance issue at the same time?

A. OSS + RDS combination
B. OSS + ECS combination
C. OSS + CDN combination
D. OSS + MTS combination

正解：B

質問 # 18
__________feature in Server Load Balancer means that it can forward the access requests from a single user to the same ECS instance within a certain period to ensure session continuity.

A. health check
B. session persistence
C. least connections scheduling
D. Weighted Round Robin

正解：B

質問 # 19
ECS is a highly flexible service. It can be used independently as a simple web server, or used with other Alibaba Cloud products, such as OSS and CDN, to provide advanced solutions. ECS can be used in applications such as:. (Choose four.)

A. no limited online storage
B. simple web applications
C. Databases
D. Official corporate websites
E. large-traffic apps

正解：B、C、D、E

解説：
Explanation
A, B, C, and D are the correct answers according to the ACA Cloud Computing by Alibaba Cloud Academy Reference Materials and documents. Comprehensive and Detailed Explanation: = A, B, C, and D are the correct answers because ECS is a highly flexible service that can be used independently as a simple web server, or used with other Alibaba Cloud products, such as OSS and CDN, to provide advanced solutions. ECS can be used in applications such as:
Official corporate websites: ECS can host official corporate websites that require high performance, stability, reliability, and scalability. ECS can also support various web frameworks and languages, such as PHP, Java, Node.js, Python, and Ruby. ECS can also be integrated with other Alibaba Cloud products, such as SLB, CDN, and WAF, to improve the security, availability, and performance of the websites1 Large-traffic apps: ECS can handle large-traffic apps that require high concurrency, low latency, and high throughput. ECS can also scale up or down based on the real-time traffic demands, and use Auto Scaling to automate the scaling process. ECS can also leverage the Alibaba Cloud network infrastructure, such as VPC, Express Connect, and Global Accelerator, to optimize the network connectivity and performance of the apps2 Databases: ECS can run various database systems, such as MySQL, PostgreSQL, MongoDB, and Redis, to provide data storage and processing capabilities for different applications. ECS can also use cloud disks or local disks as the storage media for the databases, and choose different disk types, such as SSD, ESSD, and Ultra Disk, based on the performance and cost requirements. ECS can also use RDS or PolarDB to replace the self-managed databases, and enjoy the benefits of managed database services, such as backup, recovery, monitoring, and maintenance3 Simple web applications: ECS can run simple web applications that do not require complex architectures or high availability. ECS can provide fast memory and the latest CPUs to power the web applications and achieve faster results with low latency. ECS can also use OSS to store static files, such as images, videos, and documents, and reduce the storage cost and load of the ECS instances.
E is an incorrect answer because ECS is not a storage service that provides unlimited online storage. ECS is a compute service that provides virtual machines with limited storage capacity. ECS can use OSS or NAS to expand the storage capacity, but these are separate storage services that have their own pricing and billing methods.
References: 1: Build a Corporate Website 2: Build a Large-Traffic App 3: Build a Database System : [Build a Simple Web Application] : [ECS Overview]

質問 # 20
Alibaba Cloud provides powerful security services (the same level of security services used to support Alibaba Group double 11 shopping festival). However, you have to pay first before using any of the security services.

A. False
B. True

正解：A

質問 # 21
If you are running an online ticket booking service with relatively fixed traffic, then which kind of charging mode is more suitable for you?

A. Prepaid
B. Paypal-pay
C. Pay-As-You-Go
D. bitcoin-pay

正解：A

解説：
Explanation
Prepaid is a charging mode that allows you to pay in advance for a certain amount of resources for a specified period of time. It is also known as subscription or reserved instance. Prepaid is more suitable for scenarios with relatively fixed traffic, such as an online ticket booking service, because it offers lower prices and more stable performance than pay-as-you-go. Pay-as-you-go is a charging mode that allows you to pay only for the resources you actually use on an hourly basis. It is more suitable for scenarios with unpredictable or fluctuating traffic, such as a news website or a social media platform. Paypal-pay and bitcoin-pay are not valid charging modes for Alibaba Cloud Computing products.
References: 1: Alibaba Cloud Academy, "Charging Modes",
https://edu.alibabacloud.com/elearning/lesson/ACA-Cloud-Computing-Certification/lesson-1-charging-modes

質問 # 22
Your website has high volume of traffic and sudden spikes for a very short time. In this scenario,
______________ can manage traffic peak efficiently and maintain a consistent user experience.

A. Auto Scaling
B. Server Load Balancer
C. RDS
D. VPC

正解：A

解説：
Explanation/Reference: https://www.alibabacloud.com/blog/designing-a-cloud-based-architecture-for-internet-of-vehicles- iov-series-ii_594263

質問 # 23
Alibaba Cloud China Connect is a service that can help international companies do business in China. Which of the following services is not included in China Connect?

A. Web hosting
B. ICP Support
C. Office registration support
D. Connect your service with Alibaba Group ecosystem

正解：A

解説：
Explanation
Alibaba Cloud China Connect is a service that can help international companies do business in China by providing them with the necessary infrastructure, compliance, and ecosystem support1. China Connect includes the following services1:
ICP Support: Alibaba Cloud helps you obtain the Internet Content Provider (ICP) license, which is required for any website hosted in mainland China.
Office registration support: Alibaba Cloud helps you register a legal entity in mainland China, which is required for some business scenarios such as e-commerce, online payment, and social media.
Connect your service with Alibaba Group ecosystem: Alibaba Cloud helps you leverage the Alibaba Group ecosystem, which includes platforms such as Taobao, Tmall, Alipay, and DingTalk, to reach millions of potential customers and partners in China.
However, China Connect does not include web hosting, which is a service that allows you to store and deliver your website content on Alibaba Cloud servers. Web hosting is a separate service that you can purchase from Alibaba Cloud, and it is not part of China Connect.
References: 1: Alibaba Cloud, "China Connect", https://www.alibabacloud.com/chinaconnect

質問 # 24
Anti-DDoS is one of the major features in Alibaba Cloud Security Service. Many websites have experienced different types of DDoS attacks, an accurate understanding of DDoS is crucial to protecting websites. Which of the following descriptions about DDoS attack is the most accurate one?

A. The main target for DDoS attack is the database.
B. DDoS attack will try to crack the password through a large number of attempts.
C. The main purpose of DDoS attack is to make the target server unable to provide service normally, which is one of the network attacks that are most difficult to defend.
D. The purpose of DDoS attack is to steal confidential information.

正解：C

質問 # 25
You built an online shop using Alibaba Cloud services (ECS, RDS, ...etc.) and very soon you'll have a campaign that every customer that invites 3 friends will get a 50% off coupon. To avoid HTTP flood attacks and ensure only genuine customers (not bots) joining the event, which security product should you choose?

A. Anti-DDoS Basic
B. Anti-DDoS pro
C. WAF
D. Server Guard

正解：C

解説：
After adding your website to the WAF protection list, you can enable HTTP Flood protection and select an appropriate protection mode for the website Reference: https://www.alibabacloud.com/help/doc-detail/43443.htm

質問 # 26
Company B builds a music download website based on OSS and ECS, and users can download mp3 files after registering for the website. Recently, the public network traffic to the OSS has doubled but the increase of registered users is less than 10%. After in-depth analysis, engineers find that many user download requests are raised from search engine but not the website itself. In this case, which of the following measures is thought to be able to address this issue.

A. Migrates music files from the OSS to the data disks for ECS instances.
B. Limits access sources by configuring "Anti-leech settings" of OSS bucket attributes.
C. Changes the website access mode to HTTPS.
D. Introduce SLB for extra protection.

正解：B

解説：
Reference:
http://static-aliyun-doc.oss-cn-hangzhou.aliyuncs.com/download/pdf/DNOSS11828897_en-US_intl_190202150837_public_b55986256a50380c526a35e863023ec9.pdf (55)

質問 # 27
A company wants to migrate its system to public cloud platform and they choose Alibaba Cloud. The migration process is very important and they want to ensure that everything works right. Which of the following services can the company choose?

A. Alibaba Cloud Architecture Design Training
B. Alibaba Cloud Product Operation Training
C. Aftersales Support
D. Event Management Service

正解：A

解説：
Explanation
Alibaba Cloud Architecture Design Training is a service that provides professional guidance and best practices for designing cloud architectures that meet the business requirements and goals of the company. Alibaba Cloud Architecture Design Training can help the company to understand the cloud migration process, select the appropriate Alibaba Cloud products and services, design a secure, reliable, scalable, and cost-effective cloud architecture, and implement the migration plan with minimal risks and disruptions. Alibaba Cloud Architecture Design Training can also help the company to optimize the performance and efficiency of the cloud system after the migration.
References:
Alibaba Cloud Architecture Design Training
Cloud Migration - Alibaba Cloud Solutions
ACA-Cloud1 Alibaba Exam Questions and Answers - CertLibrary

質問 # 28
Which of the following statements is wrong when comparing RDS with self-built database?

A. Self-built database supports quick deployment and elastic scaling.
B. RDS provides automatic backup while self-built database requires you to prepare storage space for backup copies and regularly verify that these copies can be restored.
C. RDS requires no O&M while self-built database requires a dedicated DBA for maintenance, which results in high HR cost.
D. RDS features a high availability of 99.95% while self-built database requires you to implement data protection, primary-standby replication, and RAID all by yourself.

正解：A

解説：
Explanation
ApsaraDB RDS is a cloud-based relational database service that provides secure, cost-effective, and scalable database solutions for various applications. RDS has many advantages over self-built databases, such as high availability, automatic backup, and easy O&M. One of the statements that is wrong when comparing RDS with self-built database is that self-built database supports quick deployment and elastic scaling. This is not true, because self-built database requires users to purchase, install, and configure hardware and software by themselves, which can be time-consuming and complex. Moreover, self-built database cannot easily adjust the computing and storage resources according to the business needs, which can lead to over-provisioning or under-provisioning. RDS, on the other hand, supports quick deployment and elastic scaling, because users can create, modify, or delete RDS instances in minutes through the console or API. Users can also scale up or down the RDS instance specifications, storage capacity, or network bandwidth without affecting the business continuity.
References:
ApsaraDB RDS
ACA Cloud Computing Certification Exam Preparation Course
Which of the following statements is NOT correct, when comparing RDS ...

質問 # 29
Which of the following ECS instance configurations can't be changed if we don't change instance type?

A. Mem size
B. Number of data disk
C. Data disk size
D. System disk size

正解：A

解説：
Explanation
= A is the correct answer because the memory size of an ECS instance is determined by the instance type, and it cannot be changed independently. If you want to change the memory size of an ECS instance, you must change the instance type to another one that has a different memory size12 B, C, and D are incorrect answers because the system disk size, data disk size, and number of data disks of an ECS instance can be changed without changing the instance type. You can use the ECS console or API to resize the system disk or data disks of an ECS instance, or add or remove data disks from an ECS instance3456 References: 1: Overview of instance families 2: Change the instance type 3: Resize disks 4: Resize a disk 5: Attach or detach data disks 6: Attach or detach a data disk

質問 # 30
SQL injection is a common application layer attack, usually through building special input parameters and pass it to web applications to steal or sabotage the application dat a. Which of the following is the target for SQL injection?

A. Confidential files on the server
B. Database
C. Pictures on server
D. Web application

正解：B

解説：
Reference:
https://www.rapid7.com/fundamentals/sql-injection-attacks/

質問 # 31
Company A builds a sales management platform based on Alibaba Cloud services, using 3 ECS instances. One of the ECS instance has MySQL installed as the database server of the platform, the other two are used as WEB servers. After some time, due to the rapid increase of employees and sales analysis requests, the performance of the platform is challenged in terms of response time. Through CloudMonitor, it is found that the average CPU usage reaches 70% for the two WEB server ECS instances and the database load reaches
75% for the database server ECS instance. In this situation, company A may choose which Alibaba Cloud services to improve the performance. (Choose two.)

A. Use content delivery network, CDN, to accelerate the caching of the platform's css, JavaScript files etc.
B. Use RDS to replace existing self-built database, in order to obtain better database performance; also creating RDS read-only instances to handle read-only requests, hence reduce the work load on master RDS instance.
C. By adding a SLB instance and increase the number of ECS instances to reduce the work load on current ECS instances.
D. Import data into OSS to share the storage load of the platform.

正解：A、B

解説：
Explanation
A and C are the correct answers because they can improve the performance of the platform by reducing the load on the ECS instances and the database server.
A is correct because using CDN can accelerate the delivery of static content such as CSS and JavaScript files, which can reduce the bandwidth consumption and latency of the ECS instances. CDN can also cache the content in edge nodes closer to the end users, which can improve the user experience and response time of the platform1 C is correct because using RDS can replace the existing self-built database, which can provide better database performance, reliability, security, and scalability. RDS can also handle the backup, recovery, monitoring, and maintenance of the database, which can reduce the management overhead and cost of the platform. Moreover, creating RDS read-only instances can handle read-only requests, which can reduce the workload on the master RDS instance and improve the database availability and performance23 References: 1: CDN Overview 2: RDS Overview 3: RDS Read-only Instances

質問 # 32
Auto Scaling is a management service that can automatically adjust elastic computing resources based on your business needs and policies. It supports adding existing ECS instances into the scaling group, whose status however must be________.