What is a system policy?
A policy defines a set of permissions that are described based on the policy structure and syntax. You can use policies to describe the authorized resource sets, authorized operation sets, and authorization conditions. Alibaba Cloud Resource Access Management (RAM) provides system policies and custom policies. All system policies are created and updated by Alibaba Cloud. You can use system policies, but you cannot modify them. You can manage and update custom policies based on your business requirements. You can create, update, and delete custom policies. During service iteration, CDN adds new permissions to system policies to support new features and capabilities. The update of a system policy affects all RAM identities to which the policy is attached, including RAM users, RAM user groups, and RAM roles. For more information about RAM policies, see Policy overview.
System policies are designed for new users to quickly get started with Alibaba Cloud products on the management console, though they also enable the use of more advanced methods like API operations or CLI commands. If you are familiar with the advanced methods, we recommend that you use custom policies to implement finer-grained control on who is permitted to call what API operations, thereby improving security.
System policies can be classified into service system policies, service role policies, and service-linked role policies. Some cloud services provide only one or two of the three types of policies. For more information, see the policy types that are described in the following section.
Service system policies
AliyunCDNFullAccess
The AliyunCDNFullAccess policy: Provides full access to Alibaba Cloud CDN via Management Console. It can be attached to RAM identities.
AliyunCDNReadOnlyAccess
The AliyunCDNReadOnlyAccess policy: Provides read-only access to Alibaba Cloud CDN via Management Console. It can be attached to RAM identities.
Service role policies
AliyunCDNLoggingRolePolicy
The AliyunCDNLoggingRolePolicy policy is the dedicated authorization policy of the AliyunCDNLoggingRole service role. By default, The CDN service will use this role to access OSS. Do not attach this policy to a RAM identity other than the service role. If a service provides precise authorization capabilities, refer to the documentation provided by the service.
Service-linked role policies
AliyunServiceRolePolicyForCDNAccessingDDoS
CDN assumes the AliyunServiceRolePolicyForCDNAccessingDDoS service-linked role to access the resources in other cloud services. The AliyunServiceRolePolicyForCDNAccessingDDoS policy is the dedicated authorization policy of the AliyunServiceRoleForCDNAccessingDDoS service-linked role. This policy is defined and used by CDN. You cannot modify or delete the policy. Do not attach this policy to a RAM identity other than the service-linked role.
AliyunServiceRolePolicyForCDNAccessingDDoS
AliyunServiceRolePolicyForCDNAccessingWAF
CDN assumes the AliyunServiceRolePolicyForCDNAccessingWAF service-linked role to access the resources in other cloud services. The AliyunServiceRolePolicyForCDNAccessingWAF policy is the dedicated authorization policy of the AliyunServiceRoleForCDNAccessingWAF service-linked role. This policy is defined and used by CDN. You cannot modify or delete the policy. Do not attach this policy to a RAM identity other than the service-linked role.
AliyunServiceRolePolicyForCDNAccessingWAF
AliyunServiceRolePolicyForCDNLogDelivery
CDN assumes the AliyunServiceRolePolicyForCDNLogDelivery service-linked role to access the resources in other cloud services. The AliyunServiceRolePolicyForCDNLogDelivery policy is the dedicated authorization policy of the AliyunServiceRoleForCDNLogDelivery service-linked role. This policy is defined and used by CDN. You cannot modify or delete the policy. Do not attach this policy to a RAM identity other than the service-linked role.
References
By default, RAM identities do not have any permissions. RAM identities can access cloud resources within an Alibaba Cloud account only after an account administrator grants the required permissions to the RAM identities. To ensure resource security, we recommend that you grant only the required permissions to the RAM identities based on the principle of least privilege. For more information, see the following topics: