ACP-Cloud1 ACP Cloud Computing Certification Questions and Answers

Once a VPC is created in Alibaba Cloud, its CIDR Block cannot be modified. This design ensures stability and network consistency within the VPC. To change the network range, a new VPC would need to be created with the desired CIDR Block.

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Alibaba Cloud Express Connect is a service that enables high-bandwidth, reliable, secure, and private connections between different networks, such as VPC networks across regions, Alibaba Cloud accounts, and on-premise data centers1. It supports different connection methods, such as physical connections, virtual border routers, and Express Cloud Connect1.

Scenario A: Intranet communication between VPCs and Smart Access Gateway in customers different branch offices. This scenario can be achieved by using Express Cloud Connect, which is based on the hardware capacities of Smart Access Gateway and provides SD-WAN capabilities1. Express Cloud Connect allows you to connect your branch offices to Alibaba Cloud through a dedicated partner backbone network, and access VPC networks in all regions1.

Scenario B: Intranet communication between a VPC and servers in an external IDC. This scenario can be achieved by using physical connections, which are dedicated network connections between on-premise data centers and VPC networks1. You can lease a line from your ISP or work with an Alibaba Cloud partner to establish a physical connection to Alibaba Cloud1. This way, you can access VPC networks in all regions with high bandwidth and low latency1.

Scenario C: Intranet communication between two VPCs in different accounts and different CIDR Blocks. This scenario can be achieved by using peering connections, which are logical connections that enable communication between VPC networks2. Peering connections support cross-region and cross-account scenarios, and allow you to connect VPC networks with different CIDR blocks2. However, peering connections are not part of Alibaba Cloud Express Connect, but a separate service called Cloud Enterprise Network2.

Scenario D: Intranet communication between two VPCs under the same account in the same region. This scenario can also be achieved by using peering connections, which are logical connections that enable communication between VPC networks2. Peering connections support intra-region and same-account scenarios, and allow you to connect VPC networks with different CIDR blocks2. However, peering connections are not part of Alibaba Cloud Express Connect, but a separate service called Cloud Enterprise Network2. References: 1: Express Connect - Alibaba Cloud 2: Introduction to Cloud Enterprise Network - Alibaba Cloud Document Center

Alibaba Cloud Auto Scaling ensures transaction completeness during scaling activities. If the intended number of ECS instances cannot be added to the scaling group, Auto Scaling rolls back the entire activity, releasing any partially added instances. This behavior prevents incomplete scaling activities, ensuring the scaling action either fully succeeds or is reverted entirely.

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

 You do not need to activate and purchase Alibaba Cloud CloudMonitor service to monitor the status of the ECS instance via Alibaba Cloud console. CloudMonitor is a service that monitors Alibaba Cloud resources and Internet applications. CloudMonitor provides a one-stop, out-of-the-box, and enterprise-class monitoring solution1. CloudMonitor collects monitor metrics of Alibaba Cloud resources and custom metrics and enables you to view and understand the usage of the cloud resources, and the health of your business2. CloudMonitor allows you to monitor the metrics of Alibaba Cloud services, detect the availability of websites hosted on ECS instances or carrier servers, and configure alert rules for specified metrics3. However, CloudMonitor is not a prerequisite for monitoring the status of the ECS instance via Alibaba Cloud console. You can monitor the status of the ECS instance via Alibaba Cloud console without activating and purchasing CloudMonitor service. You can view the basic information, configuration, security group, and tags of the ECS instance in the console. You can also view the CPU, memory, disk, and network usage of the ECS instance in the console. You can also use the Cloud Assistant feature to run commands on the ECS instance remotely4. 

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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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 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.

 A DDoS attack is a type of cyberattack that aims to exhaust the resources of a target server or network, such as bandwidth, CPU, memory, or disk space, by sending a large amount of malicious traffic or requests. This can cause the server or network to slow down, crash, or become unavailable to legitimate users. A DDoS attack is not intended to steal confidential information, crack passwords, or target databases, although these may be secondary objectives or consequences of some attacks. A DDoS attack is one of the most common and powerful threats to website security, as it can be launched from multiple sources, use various attack methods, and evade traditional defense mechanisms. According to the DDoS Attack Statistics and Trend Report by Alibaba Cloud, the proportion of volumetric attacks at 50Gbps and above has doubled, and the resources exhaustion attack reached a peak value of 3 million QPS in 2020-2021. References: DDoS Attacks: Sources, Strategies and Practices - Alibaba Cloud, DDoS Attack Statistics and Trend Report by Alibaba Cloud, Use Alibaba Cloud Anti-DDoS Service to Defend DoS Attack, Anti-DDoS Basic - Alibaba Cloud

CDN is most effective for scenarios with high repetitive access, where content is frequently requested and can be cached, such as static websites, video delivery, and application download sites. In contrast, a personal netdisk service typically involves unique, private files with low repeat access rates, making CDN less effective since the content is unlikely to be accessed by multiple users frequently, thus reducing the benefit of caching.

According to the Alibaba Cloud Auto Scaling documentation, scheduled mode allows you to configure the scheduled tasks by adding or removing ECS instances for a fixed time. This mode is suitable for scenarios where the service traffic spikes are predictable and periodic. For example, a new media company can use scheduled mode to add or reduce ECS instances dynamically to address service traffic spikes during some busy hours, such as from 07:30 to 09:00 and from 18:30 to 20:00. This mode can help simplify deployment tasks and save costs by avoiding unnecessary scaling activities. References: How Auto Scaling works - Auto Scaling - Alibaba Cloud Documentation Center.

 According to the Alibaba Cloud VPC documentation1, a virtual private cloud (VPC) is a virtual network dedicated to your Alibaba Cloud account. You have full control over your VPC, such as specifying the CIDR block, configuring route tables and gateways, and creating subnets. A VPC is an isolated network environment that provides security and flexibility for your cloud computing resources. You can use a VPC to build a secure and isolated network environment on Alibaba Cloud, design your network topology, and specify intranet IP addresses or CIDR blocks in this network environment as needed. Therefore, option B is the correct choice for your scenario. References: What is a VPC? and Alibaba Cloud Virtual Private Cloud.

Applications deployed on ECS instances that are managed by Auto Scaling should be stateless and horizontally scalable. Stateless applications do not store session data or any critical information on a single instance, allowing them to be replicated or terminated without affecting the application's overall functionality. Horizontal scalability ensures that more instances can handle additional traffic as demand increases. This setup allows Auto Scaling to add or remove instances seamlessly without requiring reconfiguration.

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.

OSS logging is a feature that allows you to record the access requests to your OSS buckets. You can enable and configure logging for a bucket in the OSS console or by using the OSS API. When logging is enabled for a bucket A, OSS automatically generates access log objects every hour and stores them in a specified bucket B. The log objects follow a predefined naming convention that includes the source bucket name, the date, the hour, and a unique string.

The documentation also states that buckets A and B can be separate buckets or the same bucket, but they must belong to the same user1. This means that you cannot store the access logs of one user’s bucket in another user’s bucket. Therefore, the correct answer is A.

References:

1: Logging - Object Storage Service - Alibaba Cloud Documentation Center

 The statement A is not correct, because self-built databases do not support quick deployment and elastic scaling. On the contrary, self-built databases require hardware procurement, data center hosting, and machine deployment, which can be time consuming and costly. Moreover, self-built databases have low resource utilization, as they have to accommodate peak traffic requirements, while RDS can scale elastically according to the actual demand. References: = ApsaraDB for RDS vs. Self-built Databases - Alibaba Cloud

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.

To improve access speeds for U.S. users, Company G can enable OSS with CDN in the West US (Silicon Valley) region. By deploying CDN in a region close to the target audience, the static content stored in OSS can be cached and delivered more efficiently. CDN caches the content at edge locations, reducing latency for users in different geographical areas. This approach is ideal for expanding the application to international markets while maintaining fast access times.

When using Alibaba Cloud SLB, you can set different weights for backend ECS instances. The higher the weight of a backend ECS instance, the more load will be assigned to it. However, the load distribution is not based on the absolute value of the weight, but on the proportion of the weight in the total weight of all healthy backend ECS instances. For example, if there are two healthy backend ECS instances with weights of 100 and 200 respectively, the first instance will receive 33.3% of the load, and the second instance will receive 66.7% of the load. Therefore, to determine the load distribution of the 5 ECS instances in the question, we need to know the weight settings of the remaining 4 ECS instances. Without this information, we cannot tell what would happen. The other options are incorrect because they are based on wrong assumptions or misunderstandings of the SLB weight setting mechanism. 

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.

SQL injection attacks primarily target databases by exploiting vulnerabilities in web applications. Attackers manipulate SQL queries to gain unauthorized access to the application's backend database, which may lead to data leakage or destruction. Although SQL injection affects the data stored in databases and not directly files or images on the server, the primary target remains the application layer through which the attack is conducted.

Security Center is a centralized security management system that dynamically identifies and analyzes security threats, and generates alerts when threats are detected. Security Center provides multiple features to ensure the security of cloud resources and servers in data centers1. Security Center can help the company to quickly resolve its security problems by providing the following benefits:

Unified security management: Security Center automatically collects various log data from the company’s services on the cloud, and implements control over found security threats. Security Center can also manage assets, attacks, vulnerabilities, and threats in the Security Center console2.

Proactive defense: Security Center supports the proactive detection and termination of mainstream ransomware, mining programs, backdoor programs, worms, malicious programs, DDoS trojans, and trojan programs. Security Center also prevents websites from being maliciously implanted with the acts that involve terrorism, politics, dark chains, trojans, and backdoors. This ensures the normal operation of web page information2.

Automated security operations: Security Center automatically traces the sources and causes of attacks. This helps the company understand the ins and outs of intrusion threats and make quick responses. Security Center also supports custom alerts and third-party data migration to the cloud in a secure manner2. References: Security Center - Alibaba Cloud, Cloud Security- Alibaba Cloud, Introduction to Security Center - Alibaba Cloud Document Center

For optimal use of SLB with Auto Scaling, enabling Health Check is essential to determine which instances are healthy and ready to handle traffic. SLB doesn’t require all backend servers to have the same OS, be in the same scaling group, or have identical configurations, as it can manage heterogeneous server setups within the same load-balancing group.

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Intelligent DNS resolution is a feature of Alibaba Cloud DNS that allows users to configure different IP addresses for the same domain name based on the geographic locations or ISPs of the visitors. This way, visitors can access the nearest or optimal server for better performance and availability. Intelligent DNS resolution does not support web page content caching, which is a function of Alibaba Cloud CDN. Alibaba Cloud CDN is a distributed network that delivers content from the origin server to the edge nodes closest to the end users, reducing the network latency and bandwidth consumption. Alibaba Cloud CDN caches the static content of the web pages, such as images, CSS, and JavaScript files, on the edge nodes, so that the users can access them faster and reduce the load on the origin server. A user will receive data from the cache in the first-time access, and then will be updated from the origin site in subsequent requests based on the cache expiration time.

References:

1: Intelligent DNS resolution - Alibaba Cloud DNS - Alibaba Cloud Documentation Center

4: Alibaba Cloud Content Delivery Network (CDN) performs content acceleration with the support of intelligent DNS resolution The following function_________is NOT included in intelligent DNS resolution.

5: Alibaba Cloud DNS:Alibaba Cloud line for intelligent DNS resolution (September 16, 2020) - Alibaba Cloud Documentation Center

 Object Storage Service (OSS) supports sub accounts, which are the accounts that belong to a parent account and share the resources of the parent account. You can allocate access permissions to different buckets for each sub account by using bucket policies or RAM policies. Bucket policies are the access control policies that are attached to buckets and specify the permissions that other users have on the resources in the buckets. RAM policies are the access control policies that are attached to RAM users or RAM user groups and specify the permissions that the RAM users or RAM user groups have on the OSS resources. References:

Object Storage Service:Overview - Alibaba Cloud

Object Storage Service:FAQ - Alibaba Cloud

Authentication - Object Storage Service - Alibaba Cloud

Using lifecycle hooks in Auto Scaling allows for custom operations, such as updating the Redis whitelist when instances are added or removed. An OOS (Operation Orchestration Service) template can automate this process, and MNS (Message Notification Service) can trigger events to inform Redis when changes occur.

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A route table is a set of rules that determine how network traffic is routed within a VPC or between different network instances1. A VRouter is a hub that connects all VSwitches in the same VPC and enables communication between them2. When you create a VPC, a VRouter and a default route table are automatically created for the VPC1. The default route table contains system routes that are automatically generated by the system based on the network topology1. The system routes cannot be modified or deleted1.

However, you can also create custom route tables for your VPC and add custom routes to them1. Custom routes are manually configured by users to route traffic to specific destinations, such as other VPCs, VBRs, VPN Gateways, or NAT Gateways1. Custom routes can be modified or deleted as needed1. You can also associate VSwitches with different route tables to implement fine-grained routing control1.

Therefore, the statement that the routing entries of the route table can not be modified manually is not correct, as it only applies to system routes, not custom routes. The other statements are correct, as each VRouter may have multiple route tables, one default and several custom1; when a VPC is deleted, the corresponding route table is also deleted3; and the default route table cannot be deleted1. References: Route table overview - Virtual Private Cloud - Alibaba Cloud Documentation Center, VRouter overview - Virtual Private Cloud - Alibaba Cloud Documentation Center, Delete a VPC - Virtual Private Cloud - Alibaba Cloud Documentation Center

Alibaba Cloud RDS offers automatic backups (with point-in-time recovery capabilities, usually up to a certain retention period), backup for both primary and secondary databases, and a dedicated team for backend operations and maintenance (O&M). Real-time patching for security vulnerabilities is generally not automatic but is managed as part of periodic updates or urgent patching requirements, making option D incorrect.

In Alibaba Cloud SLB, Layer-7 (HTTP/HTTPS) services require enabling the "X-Forwarded-For" header to retrieve the real IP address of clients, while Layer-4 (TCP/UDP) services can obtain the real IP address directly without additional settings.

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There is no limit on the number of objects that can be stored in a single OSS bucket in Alibaba Cloud. OSS is designed to support massive data storage, allowing users to store an unlimited number of files within a bucket. The only limitations are the bucket storage capacity and account-level quotas.

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Option B is correct because using Server Load Balancer (SLB) and adding additional ECS instances can help to distribute the traffic among multiple servers and improve the availability and scalability of the platform. SLB can also provide health checks and fault tolerance for the ECS instances1

Option D is correct because replacing the self-built MySQL database with ApsaraDB for RDS can provide better database performance, security, and reliability. ApsaraDB for RDS is a fully managed cloud database service that supports MySQL, SQL Server, PostgreSQL, and other engines. It can automatically handle tasks such as backup, recovery, monitoring, and patching. Using RDS read-only instances can also handle read-only requests and reduce the load on the primary database2

Option A is incorrect because importing database data into Object Storage Service (OSS) will not share the storage pressure on the platform. OSS is a cloud storage service that provides high durability, availability, and scalability for storing unstructured data such as images, videos, and documents. It is not suitable for storing structured data such as database tables. Moreover, importing data into OSS will incur additional costs and latency3

Option C is incorrect because using Content Delivery Network (CDN) will not enhance the content loading speed of the platform. CDN is a distributed network that delivers content to users based on their geographic locations, the origin of the content, and the content delivery server. It is mainly used to accelerate the delivery of static content such as images, videos, and scripts. It is not effective for dynamic content such as database queries and transactions4

References:

1: Server Load Balancer - Alibaba Cloud

2: ApsaraDB for RDS - Alibaba Cloud

3: Object Storage Service - Alibaba Cloud

4: Content Delivery Network - Alibaba Cloud

When using Auto Scaling with Server Load Balancer (SLB), both the scaling group and the SLB instance must reside in the same region. This is because region-specific configurations enable low-latency connections and proper integration between the resources, ensuring the scaling group can register with the SLB instance effectively.

Alibaba Cloud Object Storage Service (OSS) does not solely rely on RAID 0+1 redundancy technology to achieve high data reliability. OSS uses a distributed system architecture to store data across multiple devices and servers. OSS also supports cross-region replication (CRR) to replicate data across different regions for disaster recovery. OSS is designed for 99.9999999999% (12 9’s) data durability and 99.995% service availability12. References:

Object Storage Service (OSS) - Alibaba Cloud

What is OSS? - Object Storage Service - Alibaba Cloud Documentation Center

When the removal policy is set to “the earliest instance with the scaling configuration,” Auto Scaling will prioritize removing the oldest ECS instances that were created by Auto Scaling. This policy helps manage and rotate instances that may have been running the longest, ensuring newer instances remain available to handle the current load. This approach is beneficial for maintaining cost-effectiveness and operational efficiency.

 When using Alibaba Cloud SLB, users can enable the health check function to monitor the availability of the backend ECS instances. If a backend ECS instance A is running abnormally, SLB will stop forwarding requests to it and distribute them to other healthy ECS instances. This way, SLB can ensure the high availability and reliability of the service. When the backend ECS instance A is back to normal, SLB will resume forwarding requests to it. SLB performs health checks on the backend ECS instances at regular intervals and updates their status accordingly. Users can configure the health check parameters such as the protocol, port, interval, timeout, and threshold on the SLB console or by using the API. References: 1 - Health checks - Server Load Balancer - Alibaba Cloud Document Center - Health check overview

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.

According to the Alibaba Cloud Academy, Auto Scaling supports three scaling modes: manual mode, scheduled task, and cloud monitor and event-triggered task. Manual mode requires manual intervention to adjust the number of ECS instances, which is not feasible and with minimum operation efforts. Scheduled task allows you to set the time and number of ECS instances to be added or removed in advance, which is suitable for predictable traffic changes. Cloud monitor and event-triggered task allows you to set the monitoring metrics and thresholds for scaling actions, which is suitable for dynamic traffic changes. Healthy check mode is not a scaling mode, but a feature of SLB to ensure the availability of ECS instances behind the load balancer. References: : ACP Cloud Computing Certification Preparation Course - Auto Scaling, : ACP Cloud Computing Certification Preparation Course - Server Load Balancer

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.

Alibaba Cloud Object Storage Service (OSS) is a cloud storage service that allows you to store, retrieve, and manage data in the cloud. OSS provides multiple file uploading modes for different scenarios, such as simple upload, multipart upload, append upload, resumable upload, and cross-region replication. These uploading modes can be implemented by using the API or the SDK provided by OSS. Therefore, options B and D are the correct answers. Option A is not correct because the OSS management console only supports simple upload for files that are smaller than 5 GB. Option C is not correct because OSS does not support directly copying to/from OSS using portable disks. References: Object Storage Service:Simple upload, Object Storage Service:Multipart upload, Object Storage Service:OSS tools

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.

To handle high download traffic efficiently, Company F can use Object Storage Service (OSS) to store the installation package and Content Delivery Network (CDN) to distribute it. OSS provides scalable, low-cost storage, while CDN caches content at edge nodes, reducing the load on the ECS instance and improving download speeds for users. This combination helps control bandwidth costs on ECS and provides faster download speeds by serving content closer to end-users.

Not all upload methods in Alibaba Cloud OSS support resuming from a breakpoint. Only specific methods, such as multipart upload, support this feature. Small files can be uploaded using a single PUT request, while APPEND is useful for continuously updated log files. For large files, multipart uploading is recommended to handle potential interruptions.

In non-ForceDelete mode, a scaling group can only be deleted if no ECS instances exist within it and no scaling activities are currently in progress. This ensures that resources are properly released and no scaling operations are disrupted during deletion. Scheduled and event-triggered tasks (option C) and SLB/RDS integrations (option D) do not need to be removed to delete the scaling group in non-ForceDelete mode.

Auto Scaling in Alibaba Cloud supports event-triggered tasks based on CPU workload, memory utilization rate, inbound and outbound traffic, and Disk IOPS as key metrics for scaling decisions. Average system workload (option C) is not a directly supported metric, making options A, B, D, and E correct. These metrics allow Auto Scaling to respond to real-time performance needs.

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.

 A bastion host is a special-purpose computer on a network specifically designed and configured to withstand attacks. The computer generally hosts a single application, for example a proxy server, and all other services are removed or limited to reduce the threat to the computer. It is hardened in this manner primarily due to its location and purpose, which is either on the outside of a firewall or in a demilitarized zone (DMZ) and usually involves access from untrusted networks or computers. In the context of Alibaba Cloud, a bastion host can be used to securely access and manage multiple ECS instances in a VPC through the Internet. By applying an EIP and binding it to the bastion host, the administrator can use SSH or RDP protocols to log on to the bastion host from the Internet, and then use the same protocols to access other ECS instances in the VPC through the private network. This way, the administrator can avoid exposing all the ECS instances to the Internet, which would increase the risk of attacks and incur higher costs. The bastion host can also be configured with security policies and monitoring tools to enhance the protection of the ECS instances in the VPC. References: Bastion Host, Access an ECS Instance by Using a Bastion Host

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.

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?

 Cloud Firewall is a service that provides centralized protection for your cloud assets and prevents unauthorized access to your servers. Cloud Firewall can monitor and control the inbound and outbound traffic of your servers, and block malicious requests and attacks. Cloud Firewall can also detect and prevent brute force password cracking attempts by using intelligent algorithms and threat intelligence. Therefore, option A is the correct answer. References: What is Cloud Firewall?, Protect servers from brute force attacks