---
name: cephaas-about_api
title: About IBM Storage Ceph as a Service APIs
description: The IBM® Storage Ceph® as a Service Object Storage S3 API is a REST-based API for reading and writing objects.
last-updated: 2026-05-14
---

> ## Documentation Index
> The table of contents for this documentation set is at https://cloud.ibm.com/docs/cephaas?format=markdown
> The index for all IBM Cloud docs is at: https://cloud.ibm.com/docs/llms.txt
> Use these files to discover more information as needed.

# About IBM Storage Ceph as a Service APIs
{: #about-api}


IBM Storage Ceph as a Service provides you with two APIs to configure and manage your storage resources.

* [Block storage management API](https://cloud.ibm.com/docs/cephaas?topic=cephaas-about-api&format=markdown#block-storage-api)

* [Object storage administration API](https://cloud.ibm.com/docs/cephaas?topic=cephaas-about-api&format=markdown#object-storage-admin-api)

* [Object storage S3 API](https://cloud.ibm.com/docs/cephaas?topic=cephaas-about-api&format=markdown#object-storage-s3-api)


These IBM Storage Ceph as a Service APIs use IBM Cloud® Identity and Access Management for authorize and authenticate requests.

As the Cloud Identity and Access Management tokens are relatively easy to work with, `curl` is a good choice for basic testing and interaction with your storage. More information can be found in [the `curl` reference](https://cloud.ibm.com/docs/cephaas?topic=cephaas-curl&format=markdown).

The following sections describe the complete set of operations of the IBM Storage Ceph as a Service API.


## Block storage management API
{: #block-storage-api}

Use the Block storage management api to programmatically provision and manage block storage resources within the IBM Storage Ceph as a Service deployment, including volumes, hosts, and volume to host mappings.


### Block operations
{: #api-block-ops}

These operations create, delete, get information about, and control the behavior of block storage.

| Block operation                                           | Action                                            |
|:----------------------------------------------------------|:--------------------------------------------------|
| `GET /volumes`                                            | Used to retrieve a list of all block volumes.     |
| `DELETE /volumes/{id}`                                    | Deletes a volume.                                 |
| `POST /volumes`                                           | Create volume in a deployment.                    |
| `GET /volumes/{id}`                                       | Retrieves a single volume.                        |
| `PATCH /volumes/{id}`                                     | Updates the name or capacity of a volume.         |
| `GET /hosts`                                              | Retrieves a list of all hosts in the deployment   |
| `POST /hosts`                                             | Creates a new host.                               |
| `DELETE /host/{id}`                                       | Deletes a specific host.                          |
| `GET /hosts/{id}`                                         | Retrieves a specific host.                        |
| `PATCH /hosts/{id}`                                       | Updates the host information.                     |
| `POST /hosts/{id}/volume_mappings`                        | Create a Volume mapping for a host.               |
| `GET /hosts/{id}/volume_mappings/{volume_mapping_id}`     | Retrieves a single volume mapping.                |
| `GET /hosts/{id}/volume_mappings`                         | Retrieves the lists volume mappings for a host.   |
| `DELETE /hosts/{id}/volume_mappings/{volume_mapping_id}`  | Deletes the specific volume mapping.              |
| `DELETE /hosts/{id}/volume_mappings`                      | Deletes all volume mappings for a host.           |
{: caption="Block storage operation" caption-side="top"}



## Object storage administration API
{: #object-storage-admin-api}

### Administration operations
{: #api-object-admin-ops}

These operations create, delete, get information about, and control the behavior of administration objects.

| Administration operation              | Note                                                               |
|:------------------------------------  |:-------------------------------------------------------------------|
| `POST /certificates/{cert_type}`      | Create an S3 certificate.                                          |
| `PUT /certificates/{cert_type}`       | Replace or update the S3 certificate                               |
| `GET /certificates/{cert_type}`       | Retrieves the certificate status.                                  |
| `DELETE /certificates/{cert_type}`    | Deletes the S3 certificate.                                        |
| `GET /certificates`                   | Retrieves the list of configured certificates                      |
| `POST /s3_credentials/{access_key}`   | Creates S3 credential for object.                                  |
| `GET /s3_credentials`                 | Retrieves one or more S3 credentials.                              |
| `DELETE /s3_credentials/{access_key}` | Deletes the S3 credential.                                         |
{: caption="Object admin operation" caption-side="top"}


## Object storage S3 API
{: #object-storage-s3-api}

The IBM® Storage Ceph® as a Service Object Storage S3 API is a REST-based API for reading and writing objects.
{: shortdesc}

This IBM Storage Ceph as a Service API uses IBM Cloud® Identity and Access Management for authentication and authorization, and supports a subset of the S3 API for easy migration of applications to IBM Cloud.


### Object operations
{: #api-object-ops}

These operations create, delete, get information about, and control the behavior of S3 objects.

| Object operation          | Note                                                                                |
|:--------------------------|:------------------------------------------------------------------------------------|
| `DELETE` Object           | Deletes an object from a bucket.                                                    |
| `DELETE` Batch            | Deletes many objects from a bucket with one operation.                              |
| `GET` Object              | Retrieves an object from a bucket.                                                  |
| `HEAD` Object             | Retrieves an object's headers.                                                      |
| `PUT` Object              | Adds an object to a bucket.                                                         |
| `PUT` Object (Copy)       | Creates a copy of an object.                                                        |
| Begin Multipart Upload    | Creates an upload ID for a set of parts to be uploaded.                             |
| Upload Part               | Uploads a part of an object that is associated with an upload ID.                   |
| Upload Part (Copy)        | Uploads a part of an existing object that is associated with an upload ID.          |
| Complete Multipart Upload | Assembles an object from parts that are associated with an upload ID.               |
| Cancel Multipart Upload   | Cancels upload and deletes outstanding parts that are associated with an upload ID. |
| List Parts                | Returns a list of parts that are associated with an upload ID.                      |
{: caption="Object operation" caption-side="top"}


### Bucket operations
{: #api-bucket-ops}

These operations create, delete, get information about, and control the behavior of buckets.

| Bucket operation        | Note                                                                            |
|:------------------------|:--------------------------------------------------------------------------------|
| `GET` Buckets           | Used to retrieve a list of all buckets that belong to an account.              |
| `DELETE` Bucket         | Deletes an empty bucket.                                                       |
| `GET` Bucket            | Lists objects in a bucket. Limited to listing 1,000 objects at a time.         |
| `HEAD` Bucket           | Retrieves a bucket's headers.                                                  |
| `GET` Multipart Uploads | Lists multipart uploads that aren't completed or canceled.                     |
| `PUT` Bucket            | Buckets have naming restrictions. Accounts are limited to 100 buckets.         |
{: caption="Bucket operation" caption-side="top"}



More information about IBM Storage Ceph as a Service features and use-cases can be found at [ibm.com](https://www.ibm.com/products/storage-ceph){: external}.