Ceph objects are mapped to distinct and unique placement groups (PGs) that are stored by OSDs. The health of the cluster depends on the state and health of the placement groups, both individually and collectively. If a placement group is degraded then the health of the cluster is impacted, even though the rest of the PGs may be healthy and do not experience issues with client I/O. The cluster status will be HEALTH_OK only when all placement groups are in active and clean states. An unhealthy cluster manifests PGs that may be either in the active or clean state but not both—and possibly neither. The active state is required to serve client I/O, while clean indicates that the PG is not only serving I/O but also meeting other necessary requirements including replication.
Learning Ceph - Second Edition
By :
Learning Ceph - Second Edition
By:
Overview of this book
Learning Ceph, Second Edition will give you all the skills you need to plan, deploy, and effectively manage your Ceph cluster. You will begin with the first module, where you will be introduced to Ceph use cases, its architecture, and core projects. In the next module, you will learn to set up a test cluster, using Ceph clusters and hardware selection. After you have learned to use Ceph clusters, the next module will teach you how to monitor cluster health, improve performance, and troubleshoot any issues that arise. In the last module, you will learn to integrate Ceph with other tools such as OpenStack, Glance, Manila, Swift, and Cinder.
By the end of the book you will have learned to use Ceph effectively for your data storage requirements.
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Current Title:
Learning Ceph - Second Edition
Table of Contents (18 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Free Chapter
Introducing Ceph Storage
Ceph Components and Services
Hardware and Network Selection
Planning Your Deployment
Deploying a Virtual Sandbox Cluster
Operations and Maintenance
Monitoring Ceph
Ceph Architecture: Under the Hood
Storage Provisioning with Ceph
Integrating Ceph with OpenStack
Performance and Stability Tuning
Customer Reviews