Permissions and Supported Actions

By default, new IAM users do not have permissions assigned. You need to add a user to one or more groups, and attach permissions policies or roles to these groups. Users inherit permissions from the groups to which they are added and can perform specified operations on cloud services based on the permissions.

You can grant users permissions by using roles and policies. Roles are a type of coarse-grained authorization mechanism that defines permissions related to user responsibilities. Policies define API-based permissions for operations on specific resources under certain conditions, allowing for more fine-grained, secure access control of cloud resources.

Policy-based authorization is useful if you want to allow or deny the access to an API.

An account has all the permissions required to call all APIs, but IAM users must be assigned the required permissions. The permissions required for calling an API are determined by the actions supported by the API. Only users who have been granted permissions allowing the actions can call the API successfully. For example, if an IAM user wants to query ECSs using an API, the user must have been granted permissions that allow the ecs:servers:list action.

Supported Actions

IAM provides system-defined policies that can be directly used. You can also create custom policies and use them to supplement system-defined policies, implementing more refined access control. Operations supported by policies are specific to APIs. The following are common concepts related to policies:

• Permissions: Statements in a policy that allow or deny certain operations.
• APIs: REST APIs that can be called by a user who has been granted specific permissions.
• Actions: Specific operations that are allowed or denied in custom policies.
• IAM or enterprise projects: Type of projects for which an action will take effect. Policies that contain actions for both IAM and enterprise projects can be used and take effect for both IAM and Enterprise Management. Policies that only contain actions for IAM projects can be used and only take effect for IAM. For details about the differences between IAM and enterprise projects, see What Are the Differences Between IAM Projects and Enterprise Projects?

• The check mark (√) and cross symbol (x) indicate that an action takes effect or does not take effect for the corresponding type of projects. A hyphen (-) indicates that an action is irrelevant to the corresponding type of projects.
• IAM is a global service which does not involve project-based authorization.
• Some permissions support only actions and do not support APIs, such as permissions for virtual MFA device management.