I want to prepare for DevOps interviews, but I feel confused. There are too many topics: Linux, Docker, Kubernetes, Terraform, Jenkins, ArgoCD, OpenShift, cloud and SRE. Where should I start?
Start with a structured 30-day plan. Do not randomly watch videos or collect interview questions. Build a clear foundation first, practice production troubleshooting, then convert your learning into interview-ready answers and project stories.
Who this plan is for
Linux Admins
Move from server support into DevOps by connecting Linux, networking, containers and automation.
DevOps Engineers
Strengthen Kubernetes, Terraform, CI/CD, GitOps and troubleshooting answers for better roles.
OpenShift / Platform Engineers
Prepare for production platform questions around routes, SCC, operators, deployments, storage and incidents.
The 30-day learning map
Week 1: Linux + networking foundation
Most DevOps interviews silently test Linux and networking. Even Kubernetes troubleshooting becomes difficult if you do not understand processes, ports, DNS, logs, memory, disk and services.
| Day | Focus | Practice task | Interview angle |
|---|---|---|---|
| 1 | Linux process basics | Use ps, top, systemctl, journalctl | How do you troubleshoot a service not starting? |
| 2 | Logs and systemd | Check unit status, logs and restart behavior | How do you investigate repeated service failure? |
| 3 | Networking basics | Use ss, curl, dig, nc, traceroute | How do you check if app connectivity issue is DNS, port or firewall? |
| 4 | Storage and permissions | Check df, du, mount, permissions | What happens when disk is full? |
| 5 | Shell scripting | Write a small log-check or health-check script | How do you automate repeated checks? |
| 6 | Performance basics | CPU, memory, disk IO, load average | How do you identify bottlenecks? |
| 7 | Revision | Explain one real troubleshooting scenario | Turn commands into a structured answer |
Practice Week 1 inside SkillUpWorks
Use Linux, Linux Networking and Bash Scripting questions to build your foundation before moving to Kubernetes.
Week 2: Docker + Kubernetes
Should I learn Docker deeply before Kubernetes?
Learn enough Docker to understand images, containers, logs, environment variables, ports, volumes and image build failures. Then move quickly into Kubernetes because most interviews now focus on cluster behavior and troubleshooting.
Docker foundation
- Image vs container
- Dockerfile basics
- ENTRYPOINT vs CMD
- Volumes, ports and logs
- Image build failure troubleshooting
Kubernetes foundation
- Pod, Deployment, ReplicaSet
- Service, Ingress, ConfigMap, Secret
- Probes, requests, limits
- CrashLoopBackOff, ImagePullBackOff, Pending pod
- Events, logs, describe, rollout history
Minimum commands to practice
Practice Week 2 inside SkillUpWorks
Start with Docker questions, then move to Kubernetes scenario-based troubleshooting.
Week 3: Terraform + Jenkins + GitOps
Once your container and Kubernetes basics are strong, focus on how real teams provision infrastructure and deliver applications.
| Days | Topic | What to learn | Common interview question |
|---|---|---|---|
| 15–16 | Terraform | Providers, state, modules, backend, plan/apply, drift | How do you handle Terraform state in a team? |
| 17–18 | Jenkins | Declarative pipeline, agents, credentials, stages, artifacts | How do you design a CI/CD pipeline? |
| 19–20 | ArgoCD / GitOps | Git as source of truth, sync, drift, rollback, app-of-apps | What is GitOps and how is it different from Jenkins deployment? |
| 21 | Integration day | Build simple app → image → deploy to Kubernetes | Explain your end-to-end delivery flow. |
Practice Week 3 inside SkillUpWorks
Week 4: OpenShift + SRE + final interview readiness
OpenShift production concepts
- Projects, Routes, Builds, ImageStreams
- SCC and service account permissions
- Operators and cluster operators
- Storage, networking and route troubleshooting
- Application rollout and logs
SRE and incident response
- SLI, SLO and error budget basics
- Alert explanation
- Incident communication
- Postmortem thinking
- Observability: logs, metrics and traces
Project story preparation
Pick one real or lab project and prepare a clean story: problem, architecture, tools, your role, failure scenario, troubleshooting and result.
Mock interviews
Practice answering out loud. Focus on clarity, sequence, evidence, risk, rollback and communication.
Practice Week 4 inside SkillUpWorks
Daily routine: 60–90 minutes
Simple daily schedule
- 20 minutes: revise one concept.
- 30–40 minutes: run commands or simulate a scenario.
- 15–20 minutes: answer interview questions out loud.
- 10 minutes: write notes: what failed, what fixed it, what you learned.
How to know you are improving
- You explain symptoms separately from root cause.
- You mention validation commands.
- You include rollback and risk.
- You connect tools into one delivery flow.
- You stop giving only definition-based answers.
Common mistakes candidates make
Weak answer style
- Only defining terms.
- Jumping directly to restart.
- Ignoring logs and events.
- Not mentioning recent changes.
- No rollback plan.
Strong answer style
- Start with symptoms.
- Collect evidence.
- Separate possible causes.
- Validate with commands.
- Take safe action and explain rollback.
Example: how to answer a real DevOps interview question
A Kubernetes pod is in CrashLoopBackOff after a new deployment. How will you troubleshoot?
I will first check pod status, events and previous container logs. CrashLoopBackOff means the container starts and exits repeatedly, so I need to identify the exit reason. I will run describe pod to check events, probes, image, config, secret references and resource limits. Then I will check previous logs, rollout history and recent config changes. If the new version caused the issue and impact is high, I will rollback the deployment after confirming with the team. I will not blindly restart the pod because that may only hide the real issue.
Start your DevOps readiness check
Before following the 30-day plan, take the free SkillUpWorks readiness test. It shows your score, strong areas, weak areas and recommended learning path.
SkillUpWorks includes DevOps, Cloud, Linux, Kubernetes, OpenShift, Terraform, Jenkins, GitOps, SRE, AI mock interview, readiness test and hands-on project preparation.
Final recommendation
Use this 30-day plan as a practical routine. Do not only read. Practice commands, explain scenarios out loud, prepare project stories and test yourself regularly. The candidates who perform well in interviews are usually not the ones who memorize the most definitions. They are the ones who can explain how systems fail and how they troubleshoot safely.
Official references
- Kubernetes debugging documentation
- Kubernetes debugging running Pods
- Terraform state documentation
- Jenkins Pipeline documentation
- Argo CD documentation
- Red Hat OpenShift Container Platform documentation
- Google SRE book
References are included so learners can verify Kubernetes, Terraform, Jenkins, GitOps, OpenShift and SRE concepts from official or primary documentation.