DMS for Kafka Custom Policies

Custom policies can be created to supplement the system-defined policies of DMS for Kafka. For the actions that can be added for custom policies, see Permissions Policies and Supported Actions.

You can create custom policies in either of the following 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. The following section contains examples of common DMS for Kafka custom policies.

DMS for Kafka permissions policies are based on DMS. Therefore, when assigning permissions, select DMS permissions policies.
Due to data caching, a policy involving Object Storage Service (OBS) actions will take effect five minutes after it is attached to a user, user group, or project.

Example Custom Policies

Example 1: Allowing users to delete and restart instances

{
    "Version": "1.1",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "dms:instance:modifyStatus",
                "dms:instance:delete"
            ]
        }
    ]
}

Example 2: Denying instance deletion
A policy with only "Deny" permissions must be used in conjunction with other policies to take effect. If the permissions assigned to a user include both "Allow" and "Deny", the "Deny" permissions take precedence over the "Allow" permissions.

For example, if you want to assign all of the permissions of the DMS FullAccess policy to a user, except for deleting instances, you can create a custom policy to deny only instance deletion. When you apply both the DMS FullAccess policy and the custom policy denying instance deletion, since "Deny" always takes precedence over "Allow", the "Deny" will be applied for that one conflicting permission. The user will then be able to perform all operations on instances except deleting instances. The following is an example of a deny policy:
```
{
        "Version": "1.1",
        "Statement": [
                {
                        "Effect": "Deny",
                        "Action": [
                                "dms:instance:delete"
                        ]
                }
        ]
}
```