Alibaba ACA-Developer Exam Practice Test Instant Access

Question 1

Which of the following descriptions of the principles of Alibaba Cloud SSL certificate private key protection is correct?

AAlibaba Cloud uses the built-in functionality of the SSL certificate service to encrypt and store the private key to certificates private key

BThe plaintext of Alibaba Cloud's private key is usually stored on disk and backed up regularly

CAlibaba Cloud Certificate Service uses symmetric encryption to save the certificate private key

DAlibaba Cloud Certificate Service keys are loaded Into memory in plaintext format ONLY when needed

Answer : B

Question 2

A developer creates a MySQL database service on a Linux ECS instance (ECS-A), and wants to access this database service from another instance (ECS-B) in the same VPC using the private IP address bound to the ECS instance, however, the connection can't be established. What could cause this? (Number of correct answers: 2)

AThe security group for ECS-A does not have the default MySQL service port open.

BThe built-in firewall on ECS-A has rules that prohibit external access to the MySQL service port.

CNo Internet IP address is configured for ECS-A.

DThe bind-address parameter set in the my.ini configuration file of the MySQL service is commented out.

Answer : C, D

Question 3

When using Alibaba Cloud CDN, a visitor's request will first be routed to a CDN edge node, and in the event of a cache miss at this edge node, the node will fetch data from the origin site (back-to-source request). Even with this redirection, it is possible for the origin site to see the visitors real IP address. Which of the following statements about obtaining the visitor's real IP address are correct? (Number of correct answers: 2)

AA visitor's real IP address can only be obtained by modifying the site or web application.

BA visitor's real IP address is stored in the 'X-Forwarded-For' HTTP header It can be directly obtained via Apache or NGINX logs.

CIn Windows, if IIS is used, after installing the 'F5XForwardedFor' extension module, the visitor's real IP address can be seen via IIS logs.

DYou can activate the 'record visitor's real IP' function in the Alibaba Cloud CDN console, then you can directly view visitor's IP addresses from the Alibaba Cloud CDN access logs.

Answer : A, C

Question 4

What are the benefits of creating indexes on PolarDB? (Number of correct answers: 2)

AImprove the query efficiency SELECT statements.

BImprove the efficiency of DML operations such as UPDATE.

CImprove the efficiency of DDL operations.

DReduce invalid data scanning.

Answer : A, D

Question 5

Which of the following descriptions of Alibaba Cloud ECS storage are correct? (Number of correct answers: 3)

AAlibaba Cloud provides a wealth of block storage products for ECS, including Cloud Disks (virtualized storage) and Local Disks (physically attached to the server(s) that host your ECS Instances).

BBoth Local Disks and Cloud Disks use a multi-copy distributed storage mechanism, which has low latency, high performance, durability, and high reliability, and supports creation, expansion and release at any time.

CCloud Disks come In several different varieties: ESSD (Enhanced Solid State) Cloud Disks. SSD (Solid State ) Cloud Disks, and high-efficiency Cloud Disks.

DTwo types of Cloud Disks can be attached to an ECS: System Disks and Data Disks. System Disks host the ECS instances operating system.

Answer : A, B, C

Question 6

you have a Node.js based application and you plan to migrate it to Alibaba Cloud Function Compute, which of the following steps is unnecessary?

AManually install the Node. Js package in the Function Compute console

BCreate a single web application and upload the corresponding code package via the Function Compute console (or fcli)

CConfigure program startup commands and access ports in the Function Compute console

DStart and verify the application in the Function Compute console

Answer : A

Question 7

Assume that a company uses ApsaraDB for PolarDB. The company commonly queries users based on their basic information, including: addresses, company names, and ID numbers. In this scenario, what is the best practice for creating a database index (or indexes)?

ACreate a b-tree index on each column to be searched.

BCreate a hash index on each column to be searched.

CCreate a gin index for multiple fields.

DCreate a gist index for multiple fields.

Answer : A

Alibaba ACA Developer Exam Practice Test