Updated on 2025-08-18 GMT+08:00

Before You Start

Overview

Welcome to Elastic Cloud Server API Reference. An Elastic Cloud Server (ECS) is an easy-to-obtain, elastically scalable compute server that consists of a CPU, memory, image, and EVS disks. An ECS can work with a Virtual Private Cloud (VPC), virtual firewall, and multiple copies of data to build an efficient, reliable, and secure computing environment to let your services run stably. After creating an ECS, you can use it like using your local computer or physical server.

This document describes ECS application programming interfaces (APIs), including description, syntax, parameters, and examples. For details about all supported operations, see API Overview.

If you plan to access ECSs through an API, ensure that you are familiar with ECS concepts. For details, see Service Overview.

API Calling

ECSs support Representational State Transfer (REST) APIs, allowing you to call APIs using HTTPS. For details about API calling, see Calling APIs.

You can call APIs in API Explorer to view API requests and responses. In addition, the API Explorer automatically generates API calling examples to help you use APIs.

Endpoints

An endpoint is the request address for calling an API. Endpoints vary depending on services and regions. For the endpoints of all services, see Regions and Endpoints.

Constraints

  • The number of ECSs that you can create is determined by your quota. To view or increase the quota, see Quota Adjustment.
  • For more constraints, see the API description.

Concepts

  • Account

    An account is created upon successful signing up. The account has full access permissions for all of its cloud services and resources. It can be used to reset user passwords and grant user permissions. The account is a payment entity, which should not be used directly to perform routine management. For security purposes, create Identity and Access Management (IAM) users and grant them permissions for routine management.

  • User

    An IAM user is created by an account in IAM to use cloud services. Each IAM user has its own identity credentials (password and access keys).

    API authentication requires information such as the account name, username, and password.

  • Region

    Regions are divided based on geographical location and network latency. Public services, such as Elastic Cloud Server (ECS), Elastic Volume Service (EVS), Object Storage Service (OBS), Virtual Private Cloud (VPC), Elastic IP (EIP), and Image Management Service (IMS), are shared within the same region. Regions are classified into universal regions and dedicated regions. A universal region provides universal cloud services for common tenants. A dedicated region provides specific services for specific tenants.

    For details, see Region and AZ.

  • AZ

    An AZ comprises of one or more physical data centers equipped with independent ventilation, fire, water, and electricity facilities. Computing, network, storage, and other resources in an AZ are logically divided into multiple clusters. AZs within a region are interconnected using high-speed optical fibers to allow you to build cross-AZ high-availability systems.

  • Project

    A project corresponds to a region. Default projects are defined to group and physically isolate resources (including computing, storage, and network resources) across regions. Users can be granted permissions in a default project to access all resources under their accounts in the region associated with the project. If you need more refined access control, create subprojects under a default project and create resources in subprojects. Then you can assign users the permissions required to access only the resources in the specific subprojects.

    Figure 1 Project isolation model
  • Enterprise Project

    Enterprise projects group and manage resources across regions. Resources in different enterprise projects are logically isolated. An enterprise project can contain resources of multiple regions, and resources can be added to or removed from enterprise projects.

    For details about enterprise projects and about how to obtain enterprise project IDs, see Enterprise Management User Guide.

Querying Data by Page

OpenStack APIs allow users to query data using search criteria. The limit and marker parameters are added to the URL of the list request to enable the system to display query results in pages. The query results are displayed by creation time (create_time) of the records in ascending order. If the creation time is not provided, the results are displayed by object ID in ascending order.

Parameter

Type

Mandatory

Description

limit

String

No

Specifies the number of records displayed on each page. If the limit value exceeds the maximum number configured in Nova, error code 403 will be returned.

marker

String

No

Specifies the ID of the last record on the previous page. If the marker value is invalid, error code 400 will be returned.

next ref in the response indicates the URL of the next page.