Free Alibaba Cloud ACP-Cloud1 Practice Exam with Questions & Answers | Set: 4

To confirm a previously unhealthy instance is now healthy, Alibaba Cloud SLB requires three consecutive successful health checks. With a health check interval of 2 seconds and a response timeout of 5 seconds, each check cycle takes up to 5 seconds. Therefore, three successive health checks would take a minimum of 5×3=155 \times 3 = 155×3=15 seconds in total. However, because the health checks are conducted at 2-second intervals, there’s overlap, reducing the actual time to at least 11 seconds for the SLB to mark the instance as healthy.

Alibaba Cloud OSS (Object Storage Service) is designed for storing large volumes of unstructured data, such as files, images, and videos, making it an optimal solution for network disk applications. By migrating storage from ECS data disks to OSS, the team can offload storage tasks, reduce the number of ECS instances required, and significantly lower O&M costs. OSS also provides high scalability, reliability, and cost-effectiveness for such use cases.

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.

Alibaba Cloud RDS automatically deploys instances in master-slave mode (high availability) without additional configuration or charges. This ensures data redundancy and disaster recovery by maintaining synchronous data replication from the master to the slave instance.

According to the Alibaba Cloud ECS documentation1, the recommended instance type for Tomcat is ecs.c5.xlarge, which has 4 vCPUs and 4 GiB of memory. This instance type is suitable for web applications that require high performance and low latency. The recommended instance type for Memcache is ecs.r5.large, which has 2 vCPUs and 16 GiB of memory. This instance type is optimized for memory-intensive applications that require high memory bandwidth and low latency. Therefore, option D is the most recommended configuration for deploying Tomcat and Memcache on two ECS instances. References: Instance type families and Alibaba Cloud Elastic Compute Service Product Introduction

Alibaba Cloud provides comprehensive security protection covering networks, hosts, applications, databases, and content for on-cloud clients, but users still need to pay attention to security protection issues. Alibaba Cloud and its customers are jointly responsible for the security of customers’ applications built on Alibaba Cloud. With security responsibilities shared between Alibaba Cloud and its customers, Alibaba Cloud provides a secure infrastructure to decrease the enterprise security burden of customers. As such, customers can configure and use cloud products in a secure manner, thus relieving much of the underlying security burdens while allowing customers to focus more on their core business needs. However, customers still need to follow the best practices and guidelines for cloud security, such as using strong passwords, enabling multi-factor authentication, encrypting sensitive data, applying security patches, etc. Customers also need to monitor and manage the security risks and incidents of their cloud environment using Alibaba Cloud’s security products and services, such as Security Center, ActionTrail, Cloud Firewall, etc. References: Cloud Security- Alibaba Cloud, Security & Compliance Center, Shared Responsibility

Active/standby server groups are a feature of Server Load Balancer (SLB) that allows you to configure a primary ECS instance and a secondary ECS instance for the backend of an SLB instance1. When the primary instance is working properly, the traffic is only forwarded to the primary ECS. When the primary instance is down, traffic is switched to the standby instance1. This feature is supported by TCP and HTTPS listeners, but not by HTTP and UDP listeners1. TCP and HTTPS listeners support session persistence, which ensures that requests from the same client are always forwarded to the same backend server2. HTTP and UDP listeners do not support session persistence, and they use round-robin or weighted round-robin algorithms to distribute traffic among the backend servers2. References: 1: Create an active/standby server group 2: [Configure a listener]

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 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).

=================