ACA-Cloud1 Exam Dumps - Alibaba Cloud Computing Questions and Answers

Alibaba Cloud provides security services for the underlying hardware of cloud computing, such as physical security, network security, host security, and storage security. Alibaba Cloud also provides security isolation between cloud computing tenants, such as virtualization isolation, network isolation, and data isolation. These security services are part of Alibaba Cloud’s shared responsibility model, where Alibaba Cloud is responsible for the security of the cloud infrastructure, while customers are responsible for the security of their applications and data on the cloud. References: Alibaba Cloud Security Services, Alibaba Cloud Security & Compliance Center, Shared Responsibility Model

Alibaba Cloud Server Load Balancer (SLB) is a service that distributes network traffic across multiple ECS instances to improve the service capabilities of applications. SLB supports the following protocols for the listener configuration:

• HTTP: Hypertext Transfer Protocol, a stateless application-layer protocol that is used to transfer web pages and other resources over the internet.
• HTTPS: Hypertext Transfer Protocol Secure, an extension of HTTP that uses SSL/TLS encryption to provide secure communication between the client and the server.
• TCP: Transmission Control Protocol, a reliable, connection-oriented transport-layer protocol that provides reliable data delivery and error recovery.
• UDP: User Datagram Protocol, a connectionless transport-layer protocol that provides fast and efficient data transmission without guaranteeing reliability or order.

SLB does not support the following protocols:

• MPLS: Multiprotocol Label Switching, a data-carrying technique that uses labels to forward packets across a network.
• MQTT: Message Queuing Telemetry Transport, a lightweight publish/subscribe messaging protocol that is designed for constrained devices and low-bandwidth networks.

References:

• Alibaba Cloud Server Load Balancer
• ACA Cloud Computing Certification Exam Preparation Course
• Alibaba Cloud Computing Exam Question 2022

Comprehensive protocol support - ICMP, TCP, UDP, HTTP, HTTPS,

ECS can be used along with OSS to store static images, videos, and reducing storage fees. OSS is a fully managed object storage service that provides industry-leading scalability, durability, and performance. OSS can store any amount of data from anywhere, such as static images, videos, backup files, and so on. ECS is a cloud computing service that provides elastic and secure virtual cloud servers. ECS can access OSS resources by using an internal endpoint of OSS, which reduces the network latency and the traffic costs. By using ECS and OSS together, you can benefit from the following advantages1:

• Improved user experience: You can use OSS to store and deliver static content, such as images and videos, to your users. OSS integrates with CDN products to provide reliable, scalable, flexible, and cost-effective content distribution solutions. You can use ECS to run dynamic applications, such as web servers and databases, that require high performance and availability. ECS provides fast memory and the latest CPUs to help you power your cloud applications and achieve faster results with low latency.
• Reduced storage fees: You can use OSS to store large amounts of data at a low cost. OSS offers four tiers of storage: Standard, Infrequent Access, Archive, and Cold Archive. Each tier is cost-optimized for specific storage patterns. You can use lifecycle policies to automatically transition your data to the appropriate storage tier based on your business needs. You can also use Storage Capacity Unit to plan your storage budget and usage in one place. You can use ECS to scale your computing resources up or down based on real-time demands. ECS supports pay-as-you-go and different capacity reservation plans. You can also use spot instances to reduce your computing costs by up to 90%.
• Enhanced security: You can use OSS to protect your data from unauthorized access, deletion, or modification. OSS supports encryption at rest and in transit, anti-leech protection, bucket policies, RAM roles, and more. You can also use your own key (BYOK) encryption to ensure your data is encrypted when it is stored in the cloud platform. You can use ECS to secure your cloud servers from network attacks, such as DDoS and brute force attacks. ECS supports security groups, firewalls, VPCs, SSL certificates, and more. You can also use Resource Access Management (RAM) to control the access permissions of your ECS instances and OSS buckets. References: Use Alibaba Cloud CDN to accelerate access to OSS

 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

A bucket is a container for objects in Object Storage Service (OSS). Every user can create more than one bucket, but every bucket should have a unique name in OSS. There is no limitation to the number of objects inside one bucket. However, the bucket name cannot be changed after creation. You cannot customize, change, or request a namespace name change1. If you want to modify an object, you must upload a new object with the same name as the existing one to replace it2. References: 3: Create a bucket - Object Storage Service - Alibaba Cloud3 4: Manage objects in a versioning-enabled bucket - Object Storage Service - Alibaba Cloud4 1: Understanding Object Storage Namespaces - Oracle1 2: OSS Concepts - Alibaba Object Storage Service Course - Cloud Academy2

Server Load Balancer (SLB) is a ready-to-use service that seamlessly integrates with Elastic Compute Service (ECS) to manage varying traffic levels without manual intervention. SLB distributes incoming traffic among multiple ECS instances according to the configured forwarding rules, increasing the service capabilities and fault tolerance of your applications1. SLB supports Layer-4 (TCP/UDP) and Layer-7 (HTTP/HTTPS) load balancing, health checks, session persistence, cross-zone disaster recovery, and other advanced features2.

References: 1: Alibaba Cloud Academy, “Server Load Balancer”, https://edu.alibabacloud.com/elearning/lesson/ACA-Cloud-Computing-Certification/lesson-4-server-load-balancer  2: Alibaba Cloud, “What is Server Load Balancer?”, https://www.alibabacloud.com/help/doc-detail/27539.htm

 RDS allows users to create multiple databases in one RDS instance, as long as the total storage capacity and performance of the instance are not exceeded. This can help users save costs and simplify management. Users can create, delete, and manage databases in the RDS console or by using SQL commands. However, databases with the same name are not allowed in the same instance, and resources are shared among the databases in the same RDS instance, such as CPU, memory, disk, and network bandwidth. References: Operate and Manage a Relational Database on the Cloud, Alibaba RDS Course | Cloud Academy, ACA Cloud Computing Certification - Alibaba Cloud Academy

 According to the Alibaba Cloud Academy, Alibaba Cloud’s object storage service (OSS) is a cloud storage service that enables you to store, backup, and archive any amount of data in the cloud. OSS is a cost-effective, highly secure, and highly reliable cloud storage solution. The capacity of each bucket is unlimited, and there is no limit on the number of files in a single bucket. Therefore, the statement is false. References: What is OSS? - Alibaba Object Storage Service Course - Cloud Academy, Object Storage Service(OSS): Store Data Safely In The Cloud - Alibaba Cloud Blog

 A is the correct answer because Auto Scaling supports adding existing ECS instances into the scaling group, whose status however must be running. Running means that the ECS instance is in a normal state and can provide services. Auto Scaling does not support adding ECS instances that are in other states, such as created, stopped, or preparing. Created means that the ECS instance has been created but has not been started yet. Stopped means that the ECS instance has been stopped and cannot provide services. Preparing means that the ECS instance is being initialized and cannot provide services12

B, C, and D are incorrect answers because they are not valid states for adding existing ECS instances into the scaling group.

References: 1: Add existing ECS instances to a scaling group 2: ECS instance lifecycle

 Elastic Compute Service (ECS) is an IaaS offering on Alibaba Cloud that provides high-performance, stable, reliable, and scalable compute capacity in the cloud. ECS eliminates your need to invest in hardware up front. You can create as many or as few instances as you need in response to changes in requirements or popularity of your workloads. With an ever-growing selection of instance types, ECS provides broader and deeper choices to match a wide spectrum of computing needs. References: What is ECS? - Alibaba Cloud