Help Center> Scalable File Service> User Guide> Permissions Management> Creating a Custom Policy
Updated on 2024-06-27 GMT+08:00
View PDF

Creating a Custom Policy

You can create custom policies to supplement the system-defined policies of SFS. For the actions supported for custom policies, see Permissions Policies and Supported Actions.

You can create custom policies in either of the following two ways:

  • Visual editor: Select cloud services, actions, resources, and request conditions. This does not require knowledge of policy syntax.
  • JSON: Edit JSON policies from scratch or based on an existing policy.

For details, see Creating a Custom Policy. This section provides examples of common custom SFS policies.

Example Custom Policies

  • Example 1: Allowing users to create file systems
    {
        "Version": "1.1",
        "Statement": [
                {
                        "Action": [
                                "sfs:shares:createShare"
                        ],
                        "Effect": "Allow"
                }
        ]
}
  • Example 2: Denying file system deletion

    A policy with only "Deny" permissions must be used together with other policies. If the permissions granted to an IAM user contain both "Allow" and "Deny", the "Deny" permissions take precedence over the "Allow" permissions.

    The following method can be used if you need to assign permissions of the SFS FullAccess policy to a user but also forbid the user from deleting file systems. Create a custom policy for denying file system deletion, and attach both policies to the group to which the user belongs. Then, the user can perform all operations on SFS except deleting file systems. Example policy denying file system deletion:

    {
        "Version": "1.1",
        "Statement": [
                {
                        "Effect": "Deny",
                        "Action": [
                                "sfs:shares:deleteShare"
                        ]
                }
        ]
}
  • Example 3: Defining permissions for multiple services in a policy

    A custom policy can contain actions of multiple services that are all of the global or project-level type. The following is an example policy containing actions of multiple services:

    {
    "Version": "1.1",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "sfs:shares:createShare",
                "sfs:shares:deleteShare",
                "sfs:shares:updateShare"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "ecs:servers:delete"
            ]
        }
    ]
}
Parent topic: Permissions Management