DO180 Red Hat OpenShift Administration I: Operating a Production Cluster — Lesson 3: Configuration, Secrets, Storage, Probes, Scaling, and Resource Control

Learning Objectives

• Explain the structures, services, data, settings, roles, and dependencies governing ConfigMaps and Secrets.
• Implement and validate persistent storage, health probes, and resource requests and limits using reviewable evidence.
• Evaluate the condition where operators cannot explain the outcome because logs, commands, settings, and acceptance evidence were not captured consistently and select a proportionate corrective response.

Detailed Topics

• ConfigMaps applied to the course scenario, expected platform behavior, dependencies, controls, and evidence.
• Secrets applied to the course scenario, expected platform behavior, dependencies, controls, and evidence.
• persistent storage applied to the course scenario, expected platform behavior, dependencies, controls, and evidence.
• health probes applied to the course scenario, expected platform behavior, dependencies, controls, and evidence.
• resource requests and limits applied to the course scenario, expected platform behavior, dependencies, controls, and evidence.

Instructor Demonstration

The instructor traces a platform operations team onboarding containerized services onto a shared OpenShift production cluster. The walkthrough connects navigation, commands, configuration logic, system messages, and evidence captured in the OpenShift workload operations portfolio, deployment evidence, health checks, and incident runbook. It also tests the exception where operators cannot explain the outcome because logs, commands, settings, and acceptance evidence were not captured consistently.

Hands-On Exercise

Complete a controlled Red Hat exercise covering Configuration, Secrets, Storage, Probes, Scaling, and Resource Control and preserve the verified result in the OpenShift workload operations portfolio, deployment evidence, health checks, and incident runbook.

1. Confirm scope, prerequisites, versions, identities, dependencies, and acceptance criteria.
2. Execute the workflow while recording commands, settings, outputs, events, and system messages.
3. Test normal behavior, one boundary condition, and the stated exception.
4. Document corrections, evidence, ownership, retest criteria, rollback, and handover actions.

Scenario Analysis

• Identify which object, service, policy, setting, or sequence most strongly influences ConfigMaps.
• Compare two defensible responses and explain technical, security, operational, and support trade-offs.
• Determine how the OpenShift workload operations portfolio, deployment evidence, health checks, and incident runbook should be approved, retained, retested, and updated.

Troubleshooting Guidance

Start where expected behavior first differs from the observed result. Check prerequisites, identity, configuration order, version compatibility, connectivity, status, resource limits, and evidence separately. Treat “operators cannot explain the outcome because logs, commands, settings, and acceptance evidence were not captured consistently” as a hypothesis until commands, logs, settings, and retest outcomes confirm the cause.

Validation Checklist

• Required platform components, identities, permissions, settings, and dependencies are present.
• The OpenShift workload operations portfolio, deployment evidence, health checks, and incident runbook connects each conclusion to objective, reviewable evidence.
• Normal processing, a boundary condition, dependency behavior, and the stated exception were tested.
• Corrections, ownership, retest criteria, rollback, documentation, and operational handover are complete.

Lesson Outcome

Learners can apply Configuration, Secrets, Storage, Probes, Scaling, and Resource Control, explain the resulting platform behavior, and defend the outcome through the OpenShift workload operations portfolio, deployment evidence, health checks, and incident runbook.