Introduction

This section describes fine-grained permissions management for your OBS. If your account does not require individual IAM users, skip this section.

By default, new IAM users do not have any permissions assigned. You need to add a user to one or more groups, and attach IAM policies to these groups. The user then inherits permissions from the groups it is a member of. This process is called authorization. After authorization, the user can perform specified operations on OBS based on the IAM policies.

For details about user policies related to OBS, see "Permissions Management" in the "Service Overview" section of Object Storage Service User Guide. For details about the syntax and examples of IAM policies, see "IAM Policies" in the section "Permission Control" > "Permission Control Mechanisms" in the "Console Operation Guide" of Object Storage Service User Guide.

There are fine-grained policies and role-based access control (RBAC) policies. An RBAC policy consists of permissions for an entire service. Users in a group with such a policy assigned are granted all of the permissions required for that service. A fine-grained policy consists of API-based permissions for operations on specific resource types. Fine-grained policies, as the name suggests, allow for more fine-grained control than RBAC policies.

• If you want to allow or deny the access to an API, fine-grained authorization is a good choice.
• Because of the cache, it takes about 10 to 15 minutes for the RBAC policy to take effect after being granted to users and user groups. After a fine-grained OBS policy is granted, it takes about 5 minutes for the policy to take effect.

An account has all of the permissions required to call all APIs, but IAM users must have the required permissions specifically assigned. The required permissions are determined by the actions supported by the API. Only users with the policies allowing for those actions can call the API successfully. For example, if an IAM user needs to create buckets using an API, the user must have been granted permissions that allow the obs:bucket:CreateBucket action.