Chapter 1. Integrating an overcloud with Ceph Storage

Red Hat OpenStack Platform director creates a cloud environment called the overcloud. You can use director to configure extra features for an overcloud, such as integration with Red Hat Ceph Storage. You can integrate your overcloud with Ceph Storage clusters created with director or with existing Ceph Storage clusters.

For more information about Red Hat Ceph Storage, see the Red Hat Ceph Storage Architecture Guide.

1.1. Deploy the Shared File Systems service (manila) with external CephFS

Red Hat OpenStack Platform director can deploy the Shared File Systems service (manila) with CephFS. CephFS can be consumed either through the native CephFS protocol or through the NFS protocol.

For more information about these storage protocols, see CephFS with native driver and CephFS through NFS in Deploying the Shared File Systems service with CephFS through NFS.

Important

Red Hat requires a support exception to use the Shared File Systems service (manila) with CephFS through NFS to serve shares to OpenShift Container Platform through Manila CSI. For more information, contact Red Hat Support.

Important

To use native CephFS shared file systems, clients require access to the Ceph public network. When you integrate an overcloud with an existing Ceph cluster, director does not create an isolated Storage network to designate as the Ceph public network. This network is assumed to already exist. Do not provide direct access to the Ceph public network, instead, allow tenants to create a router to connect to the Ceph public network.

For more information about security considerations, see Native CephFS back end security in the CephFS Back End Guide for the Shared Files Systems Service guide.

When you use CephFS through the NFS protocol, director deploys the NFS-Ganesha gateway on Controller nodes managed by Pacemaker (PCS). PCS manages cluster availability by using an active-passive configuration.

Note

This feature is supported with Ceph Storage 4.1 or later in the Ceph 4 cycle or Ceph Storage 5.0 or later in the Ceph 5 cycle. You must install the latest version of the `ceph-ansible`package on the undercloud. For more information about how to determine the Ceph Storage release installed on your system, see Red Hat Ceph Storage releases and corresponding Ceph package versions.

For more information about how to update the ceph-ansible package on the undercloud, see Installing the ceph-ansible package.

Prerequisites

The following prerequisites are required to configure the Shared File Systems service with an external Ceph Storage cluster:

  • The external Ceph Storage cluster must have an active MDS.
  • The external Ceph Storage cluster must have a CephFS file system based on the values of the CephFS data, ManilaCephFSDataPoolName, and CephFS metadata pools, ManilaCephFSMetadataPoolName. For more information, see Creating a custom environment file.
  • The external Ceph Storage cluster must have a cephx client name and key for the Shared File Systems service. For more information, see Creating a custom environment file.

For more information about Red Hat Ceph Storage, see the Red Hat Ceph Storage File System Guide.

1.2. Configure Ceph Object Store to use external Ceph Object Gateway

Red Hat OpenStack Platform (RHOSP) director supports configuring an external Ceph Object Gateway (RGW) as an Object Store service. To authenticate with the external RGW service, you must configure RGW to verify users and their roles in the Identity service (keystone).

For more information about how to configure an external Ceph Object Gateway, see Configuring the Ceph Object Gateway to use Keystone authentication in the Using Keystone with the Ceph Object Gateway Guide.