Overview of Cluster Placement Groups

The following concepts are key to understanding the Cluster Placement Groups service.

cluster placement group

A logical entity that you associate with resources to ensure that the resources are placed in the same location and share the same physical network boundary when you create them. Collocating resources in a cluster placement group can help reduce the latency between the resources in the group.

capability

A particular type of resource or combination of resources that indicates the intended use of the cluster placement group. When creating a cluster placement group, you can specify the types of resources that you plan to deploy in that cluster placement group. The service checks that the capabilities are supported by the specified availability domain and prompts you to choose a different availability domain, if needed. Depending on the hardware, availability domains can have support for different capabilities at different times.

capacity

Physical hardware to support resources. When you create a resource, the service creating the resource finds physical hardware to meet the constraints of the request. If a service can't find available hardware within the constraints, especially when you specify that the resource must be near other resources within a particular cluster placement group, the creation process fails. To reserve capacity in a specific cluster placement group, work with the OCI account representative for the tenancy.

Cluster Placement Groups is available in all Oracle Cloud Infrastructure commercial regions in all availability domains, though support for capabilities differs by region and availability domain. See Regions and Availability Domains for the list of available regions, along with associated locations, region identifiers, region keys, and availability domains.

Cluster Placement Groups supports cluster placement groups as Oracle Cloud Infrastructure resources. Most types of resources have a unique, Oracle-assigned identifier called an Oracle Cloud ID (OCID). For information about the OCID format and other ways to identify resources, see Resource Identifiers.

You can access Cluster Placement Groups by using the Console (a browser-based interface), the command line interface (CLI), or the REST API. Instructions for the Console, CLI, and API are included in topics throughout this guide.

To access the Console, you must use a supported browser. To go to the Console sign-in page, open the navigation menu at the top of this page and click Oracle Cloud Console. You're prompted to enter the cloud tenant, your username, and your password.

For a list of available SDKs, see SDKs and the CLI. For general information about using the APIs, see REST API documentation.

Each service in Oracle Cloud Infrastructure integrates with IAM for authentication and authorization, for all interfaces (the Console, SDK or CLI, and REST API).

An administrator in your organization needs to set up groups , compartments , and policies  that control which users can access which services, which resources, and the type of access. For example, the policies control who can create new users, create and manage the cloud network, create instances, create buckets, download objects, and so on. For more information, see Getting Started with Policies.

• For details about writing Cluster Placement Groups policies, see Cluster Placement Groups IAM Policies.
• For details about writing policies for other services, see Policy Reference (for tenancies that haven't been updated to use identity domains) or Policy Reference (for tenancies that have been updated to use identity domains).

There are security best practices for Cluster Placement Groups. For more information, see Securing Cluster Placement Groups.

Cluster placement groups have service limits, but don't incur costs.

See Service Limits for a list of applicable limits and instructions for requesting a limit increase.

For instructions to view your usage level against the tenancy's resource limits, see Viewing Your Service Limits, Quotas, and Usage.

Consult with the Oracle Cloud Infrastructure account representative for the tenancy to find out whether you need a unique code to create a cluster placement group. Large capacity cluster placement groups and those with specific needs, such as certain compute core types, require advance coordination and a unique code. Then, create a cluster placement group. After you have a cluster placement group, you can then add resources to it.

• Create the required IAM policy.

• Create a cluster placement group.

• Create a Compute instance, specifying that it belongs to the cluster placement group that you created.

• Create a Block Storage volume, specifying that it belongs to the cluster placement group that you created.

If you have a deactivated resource, such as a volume replica, you can also specify a cluster placement group assignment for it during the resource's reactivation. Similarly, you can specify a cluster placement group for a backup volume when you restore it to a new volume. In any case, we recommend creating resources soon after creating the cluster placement group because capacity isn't reserved.