If the system policies do not meet your requirements, you can configure custom policies to implement the principle of least privilege. You can use custom policies to implement fine-grained access control and improve your resource security. This topic describes the common scenarios in which Database Backup (DBS) custom policies are used.
What is a custom policy?
Resource Access Management (RAM) policies are classified into system policies and custom policies. You can manage custom policies based on your business requirements.
After you create a custom policy, you must attach the policy to a RAM user, RAM user group, or RAM role. This way, the permissions that are specified in the policy can be granted to the principal.
You can delete a RAM policy that is not attached to a principal. If the RAM policy is attached to a principal, you must detach the RAM policy from the principal before you can delete the RAM policy.
Custom policies support version control. You can manage custom policy versions based on the version management mechanism provided by RAM.
References
Common scenarios and examples
Create a RAM role for data backup and restoration across Alibaba Cloud accounts.
For information about the AliyunServiceRoleForDBS service-linked role, see the Role details section of the "How do I activate DBS?" topic.
RAM authorization
We recommend that you understand the permission control requirements and detailed permissions on DBS before you create a custom policy. For more information, see RAM authorization.