Chapter 1. Introduction
Red Hat OpenStack Platform director creates a cloud environment called the overcloud. The director provides the ability to configure extra features for an Overcloud. One of these extra features includes integration with Red Hat Ceph Storage. This includes both Ceph Storage clusters created with the director or existing Ceph Storage clusters.
The Red Hat Ceph cluster described in this guide features containerized Ceph Storage. For more information about containerized services in OpenStack, see "Configuring a Basic Overcloud with the CLI Tools" in the Director Installation and Usage Guide.
1.1. Defining Ceph Storage
Red Hat Ceph Storage is a distributed data object store designed to provide excellent performance, reliability, and scalability. Distributed object stores are the future of storage, because they accommodate unstructured data, and because clients can use modern object interfaces and legacy interfaces simultaneously. At the heart of every Ceph deployment is the Ceph Storage Cluster, which consists of two types of daemons:
- Ceph OSD (Object Storage Daemon)
- Ceph OSDs store data on behalf of Ceph clients. Additionally, Ceph OSDs utilize the CPU and memory of Ceph nodes to perform data replication, rebalancing, recovery, monitoring and reporting functions.
- Ceph Monitor
- A Ceph monitor maintains a master copy of the Ceph storage cluster map with the current state of the storage cluster.
For more information about Red Hat Ceph Storage, see the Red Hat Ceph Storage Architecture Guide.
This guide only integrates Ceph Block storage and the Ceph Object Gateway (RGW). It does not include Ceph File (CephFS) storage.
1.2. Defining the Scenario
This guide provides instructions for deploying a containerized Red Hat Ceph cluster with your overcloud. To do this, the director uses Ansible playbooks provided through the
ceph-ansible package. The director also manages the configuration and scaling operations of the cluster.
1.3. Setting Requirements
If using the Red Hat OpenStack Platform director to create Ceph Storage nodes, note the following requirements for these nodes: