Question 22 Explanation

INSTANCE PRINCIPALS

The IAM service feature that enables instances to be authorized actors (or principals) to perform actions on service resources. Each compute instance has its own identity, and it authenticates using the certificates that are added to it.These certificates are automatically created, assigned to instances and rotated, preventing the need for you to distribute credentials to your hosts and rotate them.

Dynamic groups A special type of group that contains resources (such as compute instances) that match rules that you define (thus the membership can change dynamically as matching resources are created or deleted). These instances act as "principal" actors and can make API calls to services according to policies that you write for the dynamic group.

The following steps summarize the process flow for setting up and using instances as principals. The subsequent sections provide more details.

1 Create a dynamic group. In the dynamic group definition, you provide the matching rules to specify which instances you want to allow to make API calls against services.

2 Create a policy granting permissions to the dynamic group to access services in your tenancy (or compartment).

3 A developer in your organization configures the application built using the Oracle Cloud Infrastructure SDK to authenticate using the instance principals provider. The developer deploys the application and the SDK to all the instances that belong to the dynamic group.

4 The deployed SDK makes calls to Oracle Cloud Infrastructure APIs as allowed by the policy (without needing to configure API credentials).

5 For each API call made by an instance, the Audit service logs the event, recording the OCID of the instance as the value of principalId in the event log.