Book Image

Mastering Ceph

By : Nick Fisk
Book Image

Mastering Ceph

By: Nick Fisk

Overview of this book

Mastering Ceph covers all that you need to know to use Ceph effectively. Starting with design goals and planning steps that should be undertaken to ensure successful deployments, you will be guided through to setting up and deploying the Ceph cluster, with the help of orchestration tools. Key areas of Ceph including Bluestore, Erasure coding and cache tiering will be covered with help of examples. Development of applications which use Librados and Distributed computations with shared object classes are also covered. A section on tuning will take you through the process of optimisizing both Ceph and its supporting infrastructure. Finally, you will learn to troubleshoot issues and handle various scenarios where Ceph is likely not to recover on its own. By the end of the book, you will be able to successfully deploy and operate a resilient high performance Ceph cluster.
Table of Contents (12 chapters)

PG states -the good, the bad, and the ugly

Each placement group in Ceph has one or more statuses assigned to it; normally you want to see all your PGs with active+clean against them. Understanding what each state means can help us identify what is happening to PG and whether you need to take action.

The good

The following states are indication of a healthy operating cluster, no action needs to be taken.

The active state

The active state means that PG is in full health, and it is capable of accepting client requests.

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