Alibaba ACA-Cloud1 Exam Dumps

Session persistence feature in Server Load Balancer means that it can forward the access requests from a single user to the same ECS instance within a certain period to ensure session continuity. This feature is useful for applications that require users to maintain a stateful connection with the backend servers, such as online shopping or banking. Session persistence can be enabled by configuring a cookie timeout period or a source IP hash method in the Server Load Balancer console.Reference:ACA Cloud Computing Certification - Alibaba Cloud Academy,Server Load Balancer - Alibaba Cloud Academy, Session Persistence - Alibaba Cloud Documentation Center

B is the correct answer because Auto Scaling can automatically remove unhealthy ECS instances from the scaling group, and also automatically add equivalent amount of new ECS instances back to the scaling group. This feature is called Elastic Self-Health, and it can improve the availability and reliability of the scaling group. Elastic Self-Health can be enabled or disabled in the scaling group settings. When Elastic Self-Health is enabled, Auto Scaling monitors the health status of the ECS instances in the scaling group based on the health check results of the Server Load Balancer (SLB) instances that are associated with the scaling group. If an ECS instance is detected as unhealthy by SLB for a specified period of time, Auto Scaling removes the unhealthy ECS instance from the scaling group and releases it.Then, Auto Scaling triggers a scale-out event to add a new ECS instance to the scaling group to maintain the desired capacity12Reference:1:Elastic Self-Health2:Enable or disable Elastic Self-Health

Alibaba Cloud Auto Scaling service allows you to automatically adjust the number of ECS instances in a scaling group based on your business needs and scaling policies.You can set the minimum and maximum number of instances in a scaling group to limit the range of scaling actions1.When you create a scaling rule, you can specify the number of instances to be added or removed, or the expected number of instances after the scaling action2.You can also create a scheduled task to execute a scaling rule at a specified time or periodically3.

In this question, the customer sets the minimum number of instances to 6 and the maximum number of instances to 8 in the scaling group. This means that the scaling group will always have at least 6 instances and at most 8 instances. The customer also adds a scaling rule to remove 5 instances, and creates a scheduled task based on this rule. However, this scaling rule will not be executed if it violates the minimum and maximum limits of the scaling group. Therefore, when the scheduled task is activated once, the scaling group will only remove 2 instances, which is the difference between the current number of instances (8) and the minimum number of instances (6).The remaining number of instances in the scaling group will be 6, which is the correct answer.Reference:1:Create a scaling group - Auto Scaling - Alibaba Cloud Documentation Center2:Create a scaling rule - Auto Scaling - Alibaba Cloud Documentation Center3:Create a scheduled task - Auto Scaling - Alibaba Cloud Documentation Center.

Section: (none)

Explanation

An ICP license is a permit issued by the Chinese Ministry of Industry and Information Technology (MIIT) that allows websites to operate in China. An ICP license is required for any website that is hosted on a mainland China server, or that wants to use a China-based CDN service to accelerate its access in China. Therefore, you would need to apply an ICP license in the following cases:

Accelerate your Overseas Website in China: If you have a website that is hosted outside of China, but you want to use Alibaba Cloud's CDN service to improve its performance and user experience in China, you would need to apply an ICP license for your domain name. This is because Alibaba Cloud's CDN nodes are located in mainland China, and any website that uses them must comply with the Chinese regulations.

Launch your website in China: If you want to host your website on an Alibaba Cloud ECS instance or OSS bucket that is located in mainland China, you would need to apply an ICP license for your domain name. This is because any website that is hosted on a mainland China server must have an ICP license to be accessible and legal in China.

Launch your online shop in China: If you want to run an e-commerce website that sells goods or services to customers in China, you would need to apply an ICP license for your domain name. This is because any website that engages in commercial activities in China must have an ICP license to operate legally and securely in China.

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.Reference:Use Alibaba Cloud CDN to accelerate access to OSS