Free Practice Questions for Alibaba Cloud ACP-Cloud1 Exam

OSS does not use a hierarchical structure for objects, but instead uses a flat structure. All elements are stored as objects in buckets. To use OSS in the same manner in which local file systems are used, you can configure Cloud Storage Gateway (CSG).

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 The statement C is correct, because in an OSS bucket, all elements are stored as objects. An object is the basic unit of OSS storage. Each object consists of a unique key, data, and metadata. The key is the name of the object, which is used to identify the object in a bucket. The data is the content of the object, which can be any type of file, such as text, image, video, or audio. The metadata is the information about the object, such as its size, type, creation time, and custom attributes. References: = Object Storage Service:Overview - Alibaba Cloud

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

A. Elastic Compute Service (ECS) image achieve efficient and convenient deployment. This is correct because ECS images are pre-configured operating system environments that can be used to create and launch ECS instances quickly and easily. ECS images can reduce the cost and time of deploying applications on Alibaba Cloud1.

B. Utilizing Content Delivery Network (CDN) can meet the demands for redundant backup. This is incorrect because CDN is not a backup service, but a service that accelerates the delivery of content to end users by caching it at edge nodes. CDN can improve the performance and availability of applications, but it does not provide data redundancy or backup2.

C. Utilizing Server Load Balancer (SLB) and ECS instances can improve data reliability. This is correct because SLB is a service that distributes traffic among multiple ECS instances based on predefined rules. SLB can improve the availability and reliability of applications by eliminating single points of failure and ensuring that requests are routed to healthy instances3.

D. Elastic Compute Service (ECS) snapshot satisfies the needs of rapid recovery of applications and data. This is incorrect because ECS snapshot is a feature that allows users to create point-in-time backups of ECS disks. ECS snapshots can be used to restore data or create new disks, but they do not satisfy the needs of rapid recovery of applications and data. Snapshots are stored in Object Storage Service (OSS), which is a low-cost and durable storage service, but it has higher latency and lower performance than disks4.

E. Reasonable selection of Regions/Zones meets the location needs of application deployment as well as the demands for redundantly backup critical business applications and data. This is correct because regions and zones are the physical locations of Alibaba Cloud data centers. Regions are geographically isolated from each other, and zones are physically independent within the same region. Users can choose the regions and zones that best suit their application deployment needs, such as proximity to customers, compliance with local regulations, and availability of services. Users can also use multiple regions and zones to achieve redundancy and backup for their critical business applications and data.

References: 1: ECS Images 2: CDN Overview 3: SLB Overview 4: ECS Snapshots : Regions and Zones

This statement is not correct because it is not a good practice to store user access information on each ECS instance in the scaling group. This is because the ECS instances are dynamic and can be added or removed by the Auto Scaling service based on the load and demand. Therefore, the data stored on the ECS instances may be lost or inconsistent if the instances are terminated or replaced. Moreover, this approach does not provide a centralized and unified way to access and analyze the data, which may affect the accuracy and efficiency of the analysis. Therefore, it is better to use other services such as ApsaraDB for RDS, ApsaraDB for Memcache, or OSS to store the user access information in a persistent and scalable manner. References: Auto Scaling, ApsaraDB for RDS, ApsaraDB for Memcache, OSS

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.

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.

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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The port 3306 is the default port on which MySQL is usually configured. This port is used by MySQL clients and applications to connect to the MySQL server. If you are using any other port, you should allow traffic to that specific port instead. Alibaba Cloud RDS for MySQL also uses this port by default, unless you specify a different port when creating the RDS instance. You can view and modify the port number of your RDS instance in the RDS console. References: How to configure an Amazon RDS environment for MySQL, Connecting to a DB instance running the MySQL database engine, [Create an ApsaraDB RDS for MySQL instance]

Auto Scaling in Alibaba Cloud is designed to automatically adjust resources, such as ECS instances, based on the demand and scaling policies. This works best with applications that are stateless and horizontally scalable, as these applications do not rely on data stored locally on an instance, allowing them to scale in and out without affecting performance or user experience. Statelessness and horizontal scalability allow Auto Scaling to manage ECS instances efficiently without manual intervention.

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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