Book Image

Ceph Cookbook - Second Edition

By : Karan Singh, Hackett, Umrao
Book Image

Ceph Cookbook - Second Edition

By: Karan Singh, Hackett, Umrao

Overview of this book

Ceph is a unified distributed storage system designed for reliability and scalability. This technology has been transforming the software-defined storage industry and is evolving rapidly as a leader with its wide range of support for popular cloud platforms such as OpenStack, and CloudStack, and also for virtualized platforms. Ceph is backed by Red Hat and has been developed by community of developers which has gained immense traction in recent years. This book will guide you right from the basics of Ceph , such as creating blocks, object storage, and filesystem access, to advanced concepts such as cloud integration solutions. The book will also cover practical and easy to implement recipes on CephFS, RGW, and RBD with respect to the major stable release of Ceph Jewel. Towards the end of the book, recipes based on troubleshooting and best practices will help you get to grips with managing Ceph storage in a production environment. By the end of this book, you will have practical, hands-on experience of using Ceph efficiently for your storage requirements.
Table of Contents (15 chapters)

Ceph Placement Group

A Placement Group (PG) is a logical collection of objects that are replicated on OSDs to provide reliability in a storage system. Depending on the replication level of a Ceph pool, each PG is replicated and distributed on more than one OSD of a Ceph cluster. You can consider a PG as a logical container holding multiple objects, such that this logical container is mapped to multiple OSDs:

The PGs are essential for the scalability and performance of a Ceph storage system. Without PGs, it will be difficult to manage and track tens of millions of objects that are replicated and spread over hundreds of OSDs. The management of these objects without a PG will also result in a computational penalty. Instead of managing every object individually, a system has to manage the PGs with numerous objects. This makes Ceph a more manageable and less complex system.

Each...