Alibaba Cloud ACP-Cloud1 ACP Cloud Computing Certification Exam Practice Test

 The Alibaba Cloud CDN can directly accelerate access to the files stored in OSS and reduce OSS traffic costs. Alibaba Cloud CDN is a global network of points of presence (POPs) that are distributed across the globe. Alibaba Cloud CDN serves to reduce back-to-origin traffic. This in turn prevents network congestion and ensures that content is delivered with minimal latency across regions in various use cases1. Alibaba Cloud CDN caches resources from your origin servers on POPs located across the globe. Whenever customers access your resources, the resources are served from the nearest POP instead of the origin server. This helps prevent lengthy back-to-origin requests and reduces loads on origin servers, delivering better experience to your customers and reducing back-to-origin costs1. Alibaba Cloud CDN also provides IPv6 support on some POPs1. You can use Alibaba Cloud CDN to accelerate access to Object Storage Service (OSS). If you directly access OSS resources, the access speed varies based on the region in which the buckets are located and is limited by the outbound bandwidth of OSS2. The Internet traffic cost of CDN is lower than that of OSS, and the back-to-source traffic cost from CDN to OSS is also lower than a user access to OSS directly2. Therefore, using CDN can reduce the traffic cost of OSS. References: Use Alibaba Cloud CDN to accelerate access to OSS, What is Alibaba Cloud CDN?

Alibaba Cloud SLB instances are assigned a public or private IP address when created, and this IP remains unchanged for the life of the SLB instance. The IP address will only be released when the SLB instance itself is deleted.

To prevent frequent alerts when User A logs in from Shanghai, the best solution is to configure the Security Center to recognize Shanghai as a frequent login location. This will prevent unnecessary security alerts each time User A accesses the server from this location.

Alibaba Cloud OSS provides monitoring functions such as storage space monitoring, tracking service requests (like PUT and GET requests), and monitoring UV (Unique Visitors) to help analyze usage and performance. However, OSS does not specifically track the device type (e.g., PC or mobile) accessing files, making option B incorrect.

In Alibaba Cloud Object Storage Service (OSS), once a bucket is created, its name cannot be changed. This rule aligns with OSS's design to ensure global uniqueness and consistency in bucket naming across regions. Users can create multiple buckets, and each bucket can store an unlimited number of objects, provided the bucket name remains unique and immutable after creation.

Modifying the MAC address of an ECS instance’s NIC can cause network disconnection issues because Alibaba Cloud's VPC network infrastructure relies on consistent NIC configuration. Changing the MAC address may prevent the instance from being identified correctly on the network.

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To enable Internet access for ECS instances in a VPC, Alibaba Cloud users can use a public SLB with an Internet IP address (Option B) or an SLB with an Elastic IP (EIP) attached (Option C). Both methods allow the SLB instance to receive external requests and forward them to ECS instances within the VPC. Option A is incorrect because it would require a more complex setup without direct Internet access. Option D is incorrect as SLB does not support directly mounting servers from an on-premises data center.

Data Transmission Service (DTS) is a real-time data streaming service that supports data transmission between data sources such as relational databases, NoSQL, and Big Data (OLAP). DTS supports data migration, data synchronization, and change data subscription scenarios. DTS can migrate your data to and from most of the widely used commercial and open source databases. It supports homogeneous migrations such as MySQL to MySQL, as well as heterogeneous migrations between different database platforms, such as Oracle to MySQL. Migrations can be from on-premises databases to RDS or ECS, databases running on ECS to RDS, or vice versa, as well as from one RDS database to another RDS database. DTS also supports migrating data between RDS instances of different Alibaba Cloud accounts, as long as they are in the same region1. Therefore, the statement B. The data cannot be migrated is NOT correct for migrating self-built MySQL databases (running on ECS) to RDS. The other statements are correct, as the data can be imported via the Intranet, the public network, or by running mysqldump234. References:

1: Migrate Self-built Database to RDS - Alibaba Cloud

2: Migrating a Self-built MySQL Database to Alibaba Cloud RDS for MySQL with Minimal Downtime - Alibaba Cloud Community

3: Migrating Data from a Self-Managed SQL Server Database on an ECS to an ApsaraDB RDS for SQL Server Database

4: Migrate data between RDS instances of different Alibaba Cloud accounts,Data Transmission Service

Alibaba Cloud OSS (Object Storage Service) is the ideal solution for storing large volumes of video data generated by a surveillance system. OSS provides scalable, secure, and cost-effective storage that can accommodate growing data needs without the space limitations of local ECS disks. Additionally, OSS enables easy access to historical data when required, making it well-suited for video storage in use cases like surveillance.

After stopping an Alibaba Cloud Elastic Compute Service (ECS) instance, you will not be charged for the instance usage fee or the public bandwidth fee (if applicable) until you start the instance again. However, you will still be charged for the disk usage fee and the snapshot usage fee (if applicable) regardless of which region the instance is located in. This is because the disks and snapshots are still occupying the storage space and need to be billed accordingly. Therefore, the statement is false. References: 1 - Billing FAQ - Alibaba Cloud Document Center - What fees do I need to pay after I stop a Pay-As-You-Go instance?

 When the scheduled task is activated once, 4 ECS instances will be added in the scaling group. This is because the scaling rule “Add 6 ECS instances” will increase the number of instances in the scaling group to 9, which exceeds the maximum number of instances (7) that is set for the scaling group. Therefore, Auto Scaling will only add 4 ECS instances to reach the maximum number of instances. The remaining 2 ECS instances will not be added to avoid exceeding the quota. 

ECS instance monitoring provides a process monitoring feature that allows you to check the status of specific processes, such as a Python process, and set alerts for automatic notifications if the process terminates unexpectedly. This method is quicker and more efficient than writing a custom script or manually logging in to the console.

In Alibaba Cloud OSS, a bucket cannot be deleted until all contents, including files and incomplete multipart upload segments, are removed. This prevents accidental data loss by ensuring no objects remain in the bucket before deletion.

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Option A is correct because site monitoring is one of the functions provided by CloudMonitor. Site monitoring monitors the availability, connectivity, and domain name resolution of sites. It monitors the connectivity and response time of domain names, IP addresses, and ports, and sends alert notifications based on monitoring results1

Option B is correct because customized monitoring is one of the functions provided by CloudMonitor. Customized monitoring allows you to monitor the metrics of your own applications or services. You can use the CloudMonitor API or SDK to report custom metrics to CloudMonitor and view them on the CloudMonitor console. You can also configure alert rules for your custom metrics2

Option E is correct because cloud service monitoring is one of the functions provided by CloudMonitor. Cloud service monitoring monitors the metrics of Alibaba Cloud services, such as Elastic Compute Service (ECS), Object Storage Service (OSS), ApsaraDB for RDS, and Server Load Balancer (SLB). CloudMonitor collects the metrics of these services and displays them on the CloudMonitor console. You can also configure alert rules for these metrics2

Option C is incorrect because custom firewall is not a function provided by CloudMonitor. Custom firewall is a feature of Alibaba Cloud Security Center, which is a different service from CloudMonitor. Security Center provides security protection for your cloud resources and applications. Custom firewall allows you to customize firewall rules for your ECS instances and control the inbound and outbound traffic3

Option D is incorrect because operation auditing is not a function provided by CloudMonitor. Operation auditing is a feature of Alibaba Cloud ActionTrail, which is a different service from CloudMonitor. ActionTrail records the operations performed on your Alibaba Cloud resources and delivers the audit logs to OSS or Log Service for storage and analysis. Operation auditing helps you track the changes of your resources and comply with security standards4

References:

2: What is CloudMonitor? - CloudMonitor - Alibaba Cloud Documentation Center

1: Introduction to Cloud Monitor - Alibaba Security & Monitoring Course

3: [Security Center - Alibaba Cloud]

4: [ActionTrail - Alibaba Cloud]

When forwarding layer 7 (HTTP) requests, Alibaba Cloud SLB preserves the client’s real IP address by including it in the X-Forwarded-For header. This allows the backend ECS instance to access the client’s actual IP rather than the SLB’s IP address. This practice is common for maintaining accurate client IP information in HTTP forwarding scenarios.

Alibaba Cloud SLB allows users to select between private and public SLB based on business needs. A public SLB provides a public IP address for Internet-facing applications, while a private SLB provides a private IP address for internal applications within a VPC. Alibaba Cloud assigns the appropriate IP type automatically based on the user’s selection of SLB type.

The difference between public and private Server Load Balancers (SLBs) is that private SLBs connect to their backend ECS instances using the private network (Intranet) while public SLBs connect to their backend ECS instances using the public network (Internet). This is true according to the Alibaba Cloud documentation on SLB1. Public SLBs are used to distribute traffic from the Internet to ECS instances, while private SLBs are used to distribute traffic within a VPC or a classic network2. References: 1: Server Load Balancer - Alibaba Cloud Documentation Center 2: Create a Server Load Balancer instance - Server Load Balancer - Alibaba Cloud Documentation Center

When using Alibaba Cloud SLB to forward layer 7 (HTTP) service requests, SLB will replace the IP address in the HTTP header file to forward requests. Therefore, the source IP address that can be seen on the backend ECS instance is the IP address of SLB instead of the client’s real IP address. However, SLB also provides a feature called X-Forwarded-For (XFF) that can help you obtain the real IP address of the client. XFF is a standard HTTP header field that records the original IP address of the client and the proxy servers that the request passes through. You can enable XFF on the SLB console or by using the API, and then configure your backend ECS instance to parse the XFF header field and get the real IP address of the client. References: 1 - SLB overview - Alibaba Cloud Document Center - Layer 7 listeners - X-Forwarded-For

In Alibaba Cloud’s VPC architecture, a VRouter (Virtual Router) is used to connect multiple VSwitches within a VPC. The VRouter routes traffic between VSwitches, and each VSwitch in a VPC is associated with a route table managed by the VRouter. This setup enables efficient communication between subnets and applies to the entire VPC.

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Alibaba Cloud RDS supports several popular database engines, including MySQL, PostgreSQL, and SQL Server. PPAS (PostgreSQL Plus Advanced Server) is also supported but not Sybase, which is not available as an RDS option on Alibaba Cloud.

 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.

Alibaba Cloud SLB can distribute user requests to backend ECS instances, but these ECS instances do not have to have the same specification (CPU, Memory). SLB virtualizes the added group of ECS instances in the same region into an application pool, and you can manage backend servers through either the default server group, a primary server group, or VServer groups. You can add ECS instances of different specifications to the same server group or VServer group according to your needs. SLB supports weighted round-robin (WRR) and weighted least connections (WLC) algorithms to balance the load among backend servers with different weights. References:

SLB overview - Alibaba Cloud

Backend server overview - Alibaba Cloud

What is Server Load Balancer and How It Works - Alibaba Cloud

Server Load Balancer - Alibaba Cloud

Alibaba Server Load Balancer (SLB) Course - Cloud Academy

Using a single PUT upload through the console, the maximum file size is 5GB. For larger files, multipart uploading should be used, which allows uploads up to 5TB by splitting files into smaller parts.

Alibaba Cloud OSS offers Server Side Encryption to protect data at rest, enhancing security. It also supports multi-region replication with Primary/Secondary region configurations for additional data reliability and disaster recovery. Anti-DDoS is not an inherent feature of OSS, and multi-user isolation is achieved via Alibaba Cloud’s Resource Access Management (RAM).

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Alibaba Cloud CDN requires a domain name to function, as it uses DNS resolution to direct requests to the nearest edge nodes. CDN cannot directly accelerate an IP address without a domain name, so the statement is false.

Alibaba Cloud OSS is designed for scalable and secure object storage, allowing users to upload and download files through multiple interfaces, including the web console and APIs, offering flexibility and ease of use for developers and administrators.

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In Alibaba Cloud, a Virtual Private Cloud (VPC) provides isolated virtual networking environments where users can configure their own IP address ranges, CIDR blocks, routing tables, gateways, and other network elements. This functionality is critical for users who require an isolated, customizable network environment for their virtual machines in the public cloud. SDN (Software-Defined Networking) and NFV (Network Functions Virtualization) are underlying technologies, while VPN offers secure connectivity but not full virtual network management.

Alibaba Cloud OSS does not charge for data ingress, meaning there are no traffic charges for uploading files to OSS, whether through the management console or Open API. However, traffic charges may apply for data egress, i.e., downloading files from OSS.

Alibaba Cloud Security Center is designed to enhance the security of ECS instances by providing proactive monitoring, vulnerability detection, and protection against threats such as brute-force attacks. Security Center includes features such as brute-force attack detection, which will alert you to and help mitigate potential threats to your ECS instance.

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For large-scale DDoS attacks exceeding 10 Gbps, Alibaba Cloud’s Anti-DDoS Pro or Anti-DDoS Premium is recommended. These services provide advanced DDoS protection, ensuring high service availability during attacks by mitigating traffic before it reaches the server. Anti-DDoS Origin Basic Edition would not suffice for attacks at this volume.

Default and non-default VSwitches do not have the same constraints and operations. Default VSwitches have specific configurations and limitations set by Alibaba Cloud, designed to simplify initial setups. In contrast, non-default VSwitches, created by users, allow for more customized configurations and are typically used in more complex or specialized networking environments. Thus, option C is incorrect as the constraints and operations differ between default and non-default VSwitches.

Security Groups in Alibaba Cloud are VPC-specific. They can only include ECS instances within the same VPC, but they are not restricted to a single zone within the region. This means a Security Group can manage access rules across multiple ECS instances in the same VPC, regardless of the specific zone they are in, as long as they are within the same region. This ensures VPC security compliance across zones in the same region.

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 Changing an instance’s operating system requires creating a custom image or using a public image, and then replacing the system disk of the instance. This process will cause the instance to restart. Therefore, this statement is false. References: ECS User Guide: Replace the system disk (non-public image) and ECS User Guide: Replace the system disk (public image)

RDS accounts can be used to connect with the databases created on a given RDS instance. Each account can be bound with multiple databases. However, the read/write permissions of each database can be assigned to multiple RDS accounts, not just one. For example, you can create an account with read-only permission for all databases, and another account with read-write permission for a specific database. This way, you can manage the access control of your databases more flexibly and securely. References:  Introduction to ApsaraDB RDS - Alibaba Cloud Document Center - User Management - Account Permissions

The transmission acceleration service for OSS is a feature that allows you to access OSS buckets through a global acceleration endpoint, which can improve the upload and download speed of OSS data across regions. The global acceleration endpoint is a domain name that is resolved to the nearest OSS access point based on the network conditions of the client. This way, the data transmission distance is shortened and the network latency is reduced. Therefore, option C is the correct answer. References: Enable transfer acceleration, Map an acceleration endpoint

Alibaba Cloud OSS ensures high reliability and availability by maintaining multiple copies of data across different physical locations, allowing it to recover within minutes in the event of hardware failures. This redundancy mechanism provides strong data durability and service continuity.

Alibaba Cloud ECS (Elastic Compute Service) is an Infrastructure as a Service (IaaS) offering, providing users with virtualized computing resources like virtual machines. IaaS services offer fundamental cloud infrastructure such as compute, storage, and networking resources.

Cloud computing is characterized by large-scale infrastructure, high availability, on-demand service provisioning, and versatility in handling diverse applications and workloads. It supports both multi-tenant and single-tenant configurations, and although containerization is popular, cloud computing is not limited to container-based architectures.

To isolate ECS instances within different VSwitches in a VPC while allowing them to access the internet and other intranet resources, each VSwitch's instances should be in separate Security Groups. By configuring each group to allow all VPC CIDR blocks first and then restricting access to other VSwitch CIDR blocks with a higher priority rule, instances in each VSwitch are isolated without affecting the VPC's external connections. This approach follows Alibaba Cloud's Security Group best practices and CIDR-based access control within VPC environments.

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ApsaraDB for RDS is Alibaba Cloud's managed database service that simplifies O&M tasks for relational databases like MySQL. It offers built-in features for automatic backups, high availability, and Master/Slave synchronization, which reduces manual intervention and helps scale the database as traffic grows. By migrating to ApsaraDB for RDS, users can offload complex O&M responsibilities to Alibaba Cloud, ensuring a more efficient and scalable database solution for high-traffic applications.

Alibaba Cloud OSS provides three primary access permissions for buckets: Private, Public-read, and Public-read-write.

Private: Only the owner has access to read or write data.

Public-read: The owner can read and write, but others can only read.

Public-read-write: The bucket is fully open for reading and writing by all users.There is no Private-read permission in OSS access control options, so option A is incorrect.

An event-triggered task is necessary when creating scaling rules based on specific metrics such as CPU utilization. This allows Auto Scaling to monitor real-time metrics and trigger scaling actions when thresholds are met. Scheduled tasks, by contrast, are based on specific times rather than performance metrics.

Alibaba Cloud RDS uses a master-slave or primary-replica architecture to provide high availability. In the event of a master database failure, automatic failover to the standby instance generally occurs within 30 seconds, helping to minimize downtime and maintain service continuity.

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Zones in the same region support low-latency intranet communication, ideal for high-availability deployments with inter-Zone fault isolation. Placement of ECS instances in the same or different Zones depends on the disaster recovery and latency needs of the application.

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RDS for MySQL supports connections through tools that are compatible with MySQL, such as MySQL-Front, Navicat MySQL, and command-line MySQL commands. SQL Server Management Studio (SSMS) is designed for Microsoft SQL Server and is not compatible with MySQL, so option D is incorrect.

Alibaba Cloud ECS allows users to set an auto-release time for Pay-As-You-Go instances, giving flexibility in handling temporary workloads without manually releasing instances. Notably, the auto-release time can be adjusted multiple times even after the instance has been created, allowing for modifications as business needs change. This feature provides a convenient way to manage costs by automatically releasing instances when they are no longer needed. However, once the auto-release time is set, it must be adjusted or canceled if changes are required.

Even though the scaling rule is set to "Adjust to 10 ECS instances," the maximum instance limit set for the scaling group is 8. Thus, when the scheduled task is triggered, Auto Scaling will increase the number of instances up to the maximum allowed, which is 8. Therefore, the scaling group will contain 8 instances, not 10, as it adheres to the defined maximum limit.

In SLB, a Listener is configured with policies and forwarding rules that define how the load balancer will handle incoming requests, including protocol, port, and health check configurations. It does not represent an SLB instance itself or a collection of ECS instances, but it plays a crucial role in managing traffic routing and session persistence.

According to the Alibaba Cloud ECS documentation1, the Pay-As-You-Go billing method is flexible and suitable for short-term or uncertain workloads. However, it is also the most expensive option compared to other billing methods. To reduce the cost of Pay-As-You-Go instances, you can purchase a Savings Plan, which is a discount plan that offers lower prices for a fixed amount of hourly usage. A Savings Plan can be applied to any Pay-As-You-Go instance in the same region, regardless of the instance type, operating system, or zone. Therefore, option A is the most cost-effective billing method for a 10-day test, as it allows you to enjoy the flexibility of Pay-As-You-Go and the savings of a fixed commitment. References: Billing methods and Savings Plan.

During cool-down time, scaling activities in the same scaling group are temporarily locked to avoid unnecessary scaling activities. The cool-down time begins once all ECS instances in a multi-instance scaling action are added or removed.

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Alibaba Cloud SLB’s "Rewrite Cookie" mode allows selective session persistence for specific subdomains by setting and rewriting cookies as specified. For example, you can enable session persistence on vip.a.com while leaving img.a.com without it. SLB uses the rewritten cookie to direct subsequent requests to the previously assigned backend server.

Elastic Computing on Alibaba Cloud ECS includes features that allow users to quickly start or release multiple instances, upgrade bandwidth without downtime, adjust CPU and memory configurations, and perform horizontal scaling in conjunction with Server Load Balancer (SLB). However, option E is incorrect as there is a limit to the number of disks that can be attached to an ECS instance.