ACA-Cloud1 Exam Dumps : ACA Cloud Computing Associate

You can upgrade or downgrade an ECS instance’s configuration to meet your business needs. Upgrading an instance’s configuration means increasing the vCPUs, memory, bandwidth, or disk capacity of the instance. Downgrading an instance’s configuration means decreasing the vCPUs, memory, bandwidth, or disk capacity of the instance. You can change the configuration of an ECS instance by using one of the following methods1:

• Change the instance type: You can change the instance type of an ECS instance to adjust the vCPUs and memory of the instance. You can change the instance type of an ECS instance in the following scenarios2:
• Change the bandwidth configuration: You can change the bandwidth configuration of an ECS instance to adjust the network performance of the instance. You can change the bandwidth configuration of an ECS instance in the following scenarios3:
• Change the system disk or data disk: You can change the system disk or data disk of an ECS instance to adjust the disk capacity or performance of the instance. You can change the system disk or data disk of an ECS instance in the following scenarios4:

 Cloud disks are reliable because they use a distributed file management system with 3 redundant copies to provide block-level data storage for ECS instances, ensuring 99.9999999% data reliability. This means that the data stored on cloud disks is automatically replicated across three different physical servers in the same zone. If one server fails, the data can still be accessed from the other two servers. Cloud disks also support snapshot backup and recovery, which can help users restore data to a previous point in time in case of accidental deletion or corruption. References: Elastic Compute Service (ECS) - Alibaba Cloud Academy, Cloud Disk - Alibaba Cloud Documentation Center

An ECS disk can be used jointly or separately to meet the requirements of different application scenarios. ECS disks are categorized into ephemeral SSD disks and cloud disks. Compared with ephemeral SSD disks, cloud disks are more reliable as they use a triplicate distributed system to provide block-level data storage for ECS instances, ensuring 99.9999999% data reliability.

Server Load Balancer (SLB) is a service that distributes traffic among multiple ECS instances to improve the service capabilities of applications. SLB monitors the health of ECS instances in real time and automatically isolates unhealthy instances from the server pool according to the configured health check policy. This ensures that the traffic is only forwarded to healthy instances, thereby improving the availability and fault tolerance of applications. References: ACA Cloud Computing Certification - Alibaba Cloud Academy, E-Learning Courses - Alibaba Cloud Academy, Server Load Balancer - Alibaba Cloud Documentation Center