Updated on 2023-08-24 GMT+08:00

What Is ECS?

An Elastic Cloud Server (ECS) is a basic computing unit that consists of vCPUs, memory, OS, and Elastic Volume Service (EVS) disks.

You can create an ECS by specifying its vCPUs, memory, OS, and login mode. After creating an ECS, you can use it on the cloud like using your local PC or physical server. You can also modify its specifications if necessary. ECS lets your applications run in a reliable, secure, efficient computing environment.


  • Rich specifications: A variety of ECS types with custom specifications are available for different scenarios.
  • Various image types: Public, private, and shared images are available for you to choose from.
  • A broad range of disk types: High I/O, extreme SSD, and ultra-high I/O disks are provided to meet the requirements of different service scenarios.
  • Reliable data: High-throughput virtual block storage uses the distributed architecture to ensure high availability and it can be scaled out as needed.
  • Security protection: The network is isolated and protected using security group rules. Security services, such as Anti-DDoS, Web Application Firewall (WAF), and Vulnerability Scan Service (VSS) can also be used to further enhance ECS security.
  • Auto scaling: Elastic computing resources can be automatically adjusted to suit your needs.
  • Efficient O&M: ECSs can be efficiently managed through the management console, remote terminals, or APIs with full rights.
  • Cloud monitoring: Cloud Eye samples monitored metrics in real time, generates alarms when detecting problems, and immediately notifies related personnel of the alarms.
  • Load balancing: Elastic Load Balance (ELB) evenly distributes incoming traffic across ECSs to prevent overload on an individual ECS. Applications are more tolerant of errors and bursty traffic.

For more details, see ECS Advantages and ECS Application Scenarios.

System Architecture

ECS works with other products and services to provide computing, storage, and network resources.

  • You can deploy ECSs across different availability zones (AZs) that are connected over an intranet. If one AZ becomes unavailable, ECSs in other AZs can continue to provide services.
  • Virtual Private Cloud (VPC) helps you build your own dedicated network on the cloud. You can set subnets and security groups within your VPC for further isolation. You can also bind an EIP to your ECSs for Internet access.
  • With the Image Management Service (IMS), you can use an image to create ECSs. You can also use an existing ECS to create a private image and use the private image to create the same ECSs for rapid service deployment.
  • Elastic Volume Service (EVS) provides storage space. Volume Backup Service (VBS) provides data backup and restoration.
  • Cloud Eye lets you keep a close eye on the performance and resource utilization of ECSs, ensuring ECS reliability and availability.
  • Cloud Backup and Recovery (CBR) backs up data for EVS disks and ECSs, and uses snapshots and backups to restore the EVS disks and ECSs.
Figure 1 System architecture

Access Methods

You can access ECS through the web-based management console or HTTPS-based application programming interfaces (APIs).
  • Accessing ECSs through APIs

    Use this method if you intend to integrate ECSs into a third-party system for secondary development. For details, see Elastic Cloud Server API Reference.

  • Accessing ECSs through the management console

    Use this method if you are not required to integrate ECSs with a third-party system.

    Log in to the management console with your account and choose Elastic Cloud Server on the homepage.