Red Hat Ceph Storage for OpenStack – CL260 — Lesson 2: Pools, Placement Groups, RBD Block Storage, Object Gateway, and CephFS

Learning Objectives

• Configure the principal services, objects, workflows, and controls for storage pools, placement groups, and RBD.
• Apply object gateway and CephFS while preserving reviewable technical evidence.
• Recognize and correct the condition where a valid change produces the wrong outcome because variables, permissions, mapping, or sequencing are incorrect.

Detailed Topics

• storage pools: apply the concept to the course scenario, identify dependencies and controls, and record objective evidence of the result.
• placement groups: apply the concept to the course scenario, identify dependencies and controls, and record objective evidence of the result.
• RBD: apply the concept to the course scenario, identify dependencies and controls, and record objective evidence of the result.
• object gateway: apply the concept to the course scenario, identify dependencies and controls, and record objective evidence of the result.
• CephFS: apply the concept to the course scenario, identify dependencies and controls, and record objective evidence of the result.

Instructor Demonstration

The instructor demonstrates pools, placement groups, rbd block storage, object gateway, and cephfs by tracing architecture, commands, configuration, system messages, and evidence. The walkthrough tests how a valid change produces the wrong outcome because variables, permissions, mapping, or sequencing are incorrect and explains how to isolate the cause without masking related issues.

Hands-On Exercise

Implement the core workflow for Pools, Placement Groups, RBD Block Storage, Object Gateway, and CephFS and add the verified result to the Ceph cluster build record, OpenStack integration design, health evidence, capacity plan, and recovery runbook.

1. Confirm scope, versions, access, dependencies, assumptions, and acceptance criteria.
2. Perform the workflow while recording commands, configuration, output, events, and decisions.
3. Test the normal path and one course-specific exception or boundary condition.
4. Retest the correction and document rollback, ownership, and follow-up actions.

Scenario Analysis

• Identify which dependency most strongly influences storage pools in the stated scenario.
• Compare two approaches for object gateway and explain the security, reliability, performance, and support trade-offs.
• Decide what evidence must be retained in the Ceph cluster build record, OpenStack integration design, health evidence, capacity plan, and recovery runbook before operational acceptance.

Troubleshooting Guidance

Begin with the first observable difference from the expected result. Check configuration, permissions, sequence, connectivity, and functional behavior separately, then correlate logs, events, commands, metrics, and configuration history. Treat the assumption that a valid change produces the wrong outcome because variables, permissions, mapping, or sequencing are incorrect as a hypothesis until a reproducible retest confirms the cause.

Validation Checklist

• The required configuration, permissions, sequence, connectivity, and functional behavior were checked and recorded.
• The normal path and a course-specific exception were tested.
• The Ceph cluster build record, OpenStack integration design, health evidence, capacity plan, and recovery runbook links conclusions to commands, configuration, logs, metrics, or other objective evidence.
• Corrective actions, rollback, ownership, and handover notes are complete.

Lesson Outcome

Learners can apply Pools, Placement Groups, RBD Block Storage, Object Gateway, and CephFS, explain the observed platform behavior, and support the result with a reviewable Ceph cluster build record, OpenStack integration design, health evidence, capacity plan, and recovery runbook.