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 (SFS Capacity-Oriented)

Example 1: Grant permission to create file systems.

{
        "Version": "1.1",
        "Statement": [
                {
                        "Action": [
                                "sfs:shares:createShare"
                        ],
                        "Effect": "Allow"
                }
        ]
}

Example 2: Grant permission to deny 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"
            ]
        }
    ]
}

Example Custom Policies (General Purpose File System)

Example 1: Grant permission to create general purpose file systems.

{
        "Version": "1.1",
        "Statement": [
                {
                        "Action": [
                                "sfs3:fileSystem:createFileSystem"
                        ],
                        "Effect": "Allow"
                }
        ]
}

Example 2: Grant permission to deny general purpose 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.

Assume that you want to grant the permissions of the SFS3 FullAccess policy to a user but want to prevent them from deleting general purpose file systems. You can create a custom policy for denying file system deletion, and attach this policy together with the SFS3 FullAccess policy to the user. As an explicit deny in any policy overrides any allows, the user can perform all operations on general purpose file systems excepting deleting them. Example policy denying file system deletion:
```
{
        "Version": "1.1",
        "Statement": [
                {
                        "Effect": "Deny",
                        "Action": [
                                "sfs3:fileSystem:deleteFileSystem"
                        ]
                }
        ]
}
```