DevOps Interview Prep: Questions, Answers, Code Examples

Andrei Dumitrescu
Andrei Dumitrescu
hero image

DevOps is the backbone of modern software development, breaking down silos between development and operations to enable faster, more reliable releases.

But landing a DevOps role takes more than technical know-how—you need to demonstrate a solid grasp of core principles, essential tools, and real-world practices that employers expect in interviews.

The good news? This guide walks you through the most common DevOps interview questions, from beginner to advanced, explaining not just what to say but why interviewers ask them and how to craft strong, confident answers.

Whether you're brushing up before an interview or filling in knowledge gaps, this guide has you covered.

Let’s dive in.

Sidenote: If you do find that you’re struggling with the questions in this guide, or perhaps feel that you could use some more training and want to build some more impressive projects for your portfolio, then check out my complete DevOps course.

learn devops

I guarantee that this is the most comprehensive and up-to-date DevOps Bootcamp that you can find to learn and master Linux, from scratch.

Not only do we cover the basics so you have a concrete foundation, but this course ensures that you’ll actually retain what you're learning by giving you the chance to apply Linux in real-world scenarios by configuring a Linux Server from scratch in the cloud!

This DevOps Bootcamp will take you from an absolute beginner to getting hired as a confident and effective Linux System Administrator.

With that out of the way, let’s get into the questions.

Beginner DevOps Interview Questions

#1. What is DevOps, and why is it important?

DevOps is a set of practices and cultural philosophies that aim to break down the traditional silos between development (Dev) and operations (Ops) teams.

By focusing on collaboration, automation, and continuous delivery, DevOps helps organizations release software faster, more reliably, and with fewer failures.

Why it matters

This question is designed to test your fundamental knowledge of DevOps. Interviewers want to see if you understand not just what DevOps is, but why it’s essential in modern software development. A strong answer should explain how DevOps improves collaboration, speeds up releases, and reduces failures.

For example

In a traditional IT setup, developers write code and pass it to an operations team to deploy. This process often leads to miscommunication, delays, and bugs.

With DevOps, developers and operations teams work together from the start, using automation and shared tools to deploy changes frequently and reliably. This reduces the risk of failures and allows companies to release updates faster.

#2. What are the key principles of DevOps?

DevOps is built on several core principles that drive efficiency, collaboration, and automation in software development and IT operations. These principles ensure that teams can develop, test, deploy, and monitor software quickly and reliably.

The key DevOps principles include:

  • Collaboration & Communication – Breaking down silos between development and operations teams, ensuring shared ownership of software delivery
  • Automation – Reducing manual tasks in software development, testing, deployment, and monitoring to improve speed and consistency
  • Continuous Integration & Continuous Deployment (CI/CD) – Frequently integrating and deploying code changes to deliver updates faster with minimal risk
  • Infrastructure as Code (IaC) – Managing infrastructure using code, enabling consistent, repeatable, and scalable deployments
  • Monitoring & Feedback – Continuously tracking system performance, identifying issues early, and making iterative improvements

Why it matters

Interviewers ask this question to test your understanding of the DevOps mindset beyond just tools and technologies. A strong answer should emphasize that DevOps is not just about automation—it’s about building a culture of collaboration, feedback, and continuous improvement.

For example

A company struggling with long deployment cycles might adopt CI/CD to automate testing and releases, reducing deployment time from weeks to hours. Additionally, Infrastructure as Code (IaC) can eliminate inconsistencies in cloud environments, ensuring that staging and production are identical, reducing unexpected failures.

#3. What is CI/CD, and why is it used in DevOps?

CI/CD stands for Continuous Integration (CI) and Continuous Deployment (CD), a DevOps practice that ensures code is frequently integrated, tested, and deployed in an automated and reliable manner.

  • Continuous Integration (CI) – Developers frequently merge code changes into a shared repository, where automated tests check for errors. This ensures that new code integrates smoothly without breaking the existing system
  • Continuous Deployment (CD) – Once changes pass testing, they are automatically deployed to production without manual intervention, allowing for rapid, stable releases. Some companies use Continuous Delivery, where deployments require approval before release

Why it matters

CI/CD is a core DevOps practice because it eliminates the traditional bottlenecks of manual testing and deployments, allowing teams to deliver software faster with fewer errors.

Interviewers ask this question to see if you understand how automation enhances efficiency in the software development lifecycle.

For example

A company that releases new features every two weeks can implement a CI/CD pipeline where every code change is automatically tested and deployed. This removes the need for manual deployments, reduces downtime, and allows teams to deliver updates daily instead of waiting for scheduled releases.

#4. What are some popular DevOps tools, and what do they do?

DevOps relies on a variety of tools to automate processes, improve collaboration, and streamline software delivery. Here are some widely used tools across different DevOps categories:

  • Operating System & Shell Scripting:
    • Linux – The backbone of most cloud and DevOps environments, used for managing servers, automation, and deployments
    • Bash – A powerful scripting language commonly used for writing automation scripts and managing system tasks
  • Version Control:
    • Git, GitHub, GitLab – Track code changes, manage collaboration, and enable rollback if needed
  • Infrastructure as Code (IaC):
    • Terraform – Automates infrastructure provisioning across cloud providers, ensuring scalable and repeatable deployments
  • CI/CD Pipelines:
    • Jenkins, GitHub Actions, GitLab CI/CD, CircleCI – Automate software build, test, and deployment processes
  • Configuration Management & Infrastructure Automation:
    • Ansible, Puppet, Chef – Automate infrastructure setup, manage configurations, and ensure consistency across environments
  • Containerization & Orchestration:
    • Docker – Package applications with their dependencies into portable containers
    • Kubernetes – Orchestrate and manage containers, handling deployment, scaling, and networking
  • Monitoring & Logging:
    • Prometheus, Grafana – Collect and visualize system metrics to track performance and troubleshoot issues
    • ELK Stack (Elasticsearch, Logstash, Kibana) – Centralize, analyze, and visualize logs to improve system observability

Why it matters

Interviewers ask this to see if you understand the DevOps toolchain and how different tools fit into automation and software delivery. While you don’t need hands-on experience with every tool, you should be able to explain why they are used in DevOps workflows.

#5. What is Infrastructure as Code (IaC), and why is it important?

Infrastructure as Code (IaC) is the practice of managing and provisioning infrastructure through code, rather than manual processes.

Using declarative or imperative scripting, IaC allows teams to define infrastructure configurations in files that can be version-controlled and automated.

Why it matters

IaC is critical in DevOps because it ensures that infrastructure is scalable, repeatable, and consistent across environments. Instead of manually setting up servers, networks, and storage, teams can define infrastructure in code, making deployments faster and reducing human errors.

For example

A company using Terraform can write a configuration file that provisions multiple cloud instances, databases, and networking rules.

Instead of manually clicking through a cloud provider’s UI, the team can apply the Terraform script and deploy identical infrastructure in seconds, ensuring consistency across development, staging, and production.

#6. What is version control, and why is Git widely used in DevOps?

Version control is a system that tracks changes to code over time, allowing teams to collaborate, revert to previous versions, and maintain a history of modifications. It ensures that developers can work on different features simultaneously without overwriting each other's changes.

Git is the most widely used distributed version control system, enabling multiple developers to work on the same project while maintaining a full history of changes.

Key Git features relevant to DevOps:

  • Branching & Merging – Developers can create separate branches to work on features and merge them once completed
  • Distributed Nature – Every developer has a full copy of the repository, allowing offline work
  • Integration with CI/CD – Git is essential for automating CI/CD pipelines, triggering builds and tests on every code commit

Why it matters

Version control is fundamental to DevOps workflows. Interviewers ask this question to test if you understand how Git enables collaboration and automation in modern development.

For example

A team using GitHub and Jenkins can set up a CI/CD pipeline that automatically triggers tests and deployments every time new code is pushed to the main branch. This reduces manual effort and ensures faster, more reliable releases.

#7. What are microservices, and how do they relate to DevOps?

Microservices is an architectural approach where applications are built as a collection of small, loosely coupled services, each responsible for a specific function. These services communicate via APIs and can be independently developed, deployed, and scaled.

How microservices relate to DevOps:

  • Faster Deployments – Each service can be updated independently, reducing the risk of large-scale failures
  • Scalability – Teams can scale individual services instead of the entire application
  • Automation & CI/CD – Microservices work well with DevOps CI/CD pipelines, enabling frequent, automated deployments
  • Containerization & Orchestration – Microservices are often deployed using Docker and managed with Kubernetes, aligning with DevOps automation practices

Why it matters

Companies adopting DevOps often shift to microservices to improve deployment agility and scalability. Interviewers ask this to see if you understand how architecture choices affect DevOps practices.

For example

A traditional monolithic application requires deploying the entire system when making changes. With microservices, a team can deploy only the affected service, ensuring faster updates with minimal downtime.

This approach is widely used by Netflix, Amazon, and Uber to scale their systems efficiently.

#8. What is containerization, and how does it differ from virtualization?

Containerization is the process of packaging an application and its dependencies into a lightweight, portable container that runs consistently across different environments.

Containers share the host OS kernel but remain isolated, ensuring applications run the same way in development, testing, and production.

Difference between containerization and virtualization

Feature Virtualization Containerization
Architecture Runs entire OS on a hypervisor Shares host OS, runs isolated apps
Resource Usage Requires more system resources Lightweight, consumes fewer resources
Boot Time Slow (minutes) Fast (seconds)
Isolation Stronger, each VM has its own OS Weaker but sufficient for most applications
Example Tools VMware, VirtualBox, KVM Docker, Podman, LXC

Why it matters

Containers enable faster deployments, easier scaling, and consistent environments, making them essential for CI/CD pipelines and cloud-native applications.

Interviewers ask this question to see if you understand why DevOps teams prefer containers over traditional virtual machines.

For example

A developer can build a Docker container on their laptop, and the same container can run identically in AWS, Azure, or Kubernetes clusters. This eliminates the classic "it works on my machine" problem, ensuring consistency across environments.

#9. What is orchestration in DevOps, and why is Kubernetes widely used?

Orchestration in DevOps automates the deployment, management, scaling, and networking of containers to ensure applications run smoothly across multiple environments. Without orchestration, managing hundreds or thousands of containers manually would be inefficient and error-prone.

Kubernetes (K8s) is the most popular container orchestration tool because it:

  • Automates scaling – Dynamically adjusts the number of running containers based on demand
  • Ensures high availability – Distributes workloads across nodes to prevent failures
  • Manages networking & service discovery – Allows containers to communicate securely
  • Handles self-healing – Automatically restarts failed containers

Why it matters

Orchestration is essential for running containerized applications at scale. Interviewers ask this to see if you understand why DevOps teams use Kubernetes to automate container management.

For example

A company running microservices in Docker containers can use Kubernetes to automatically scale services up during peak traffic and down when demand drops. This ensures optimal resource usage and cost efficiency without manual intervention.

#10. What is the difference between DevOps and Agile?

While DevOps and Agile share similar goals — faster software delivery, collaboration, and continuous improvement. However, they focus on different aspects of the development lifecycle.

Feature Agile DevOps
Focus Software development process Software development + operations
Goal Faster, iterative development Faster, automated delivery & deployment
Methodology Uses Scrum, Kanban, sprints Uses CI/CD, automation, infrastructure as code
Team Structure Developers work in small iterations Dev & Ops collaborate throughout lifecycle
Deployment Development is iterative, but deployment may still be manual Automates the full pipeline from code to production

Why it matters

Many people confuse Agile and DevOps. Interviewers ask this to see if you understand how they complement each other. Agile focuses on development speed, while DevOps ensures that software reaches production quickly and reliably.

For example

A team using Agile might work in two-week sprints to develop new features. But without DevOps practices like CI/CD and automated testing, deploying those features could still be slow and risky.

DevOps ensures those Agile iterations reach users efficiently by automating deployments.

Intermediate DevOps Interview Questions

#11. What is a DevOps pipeline, and what are its key stages?

A DevOps pipeline is a set of automated processes that allow developers to build, test, and deploy software efficiently. It ensures that code changes move through development, testing, and production with minimal manual intervention.

Key stages of a DevOps pipeline:

  1. Source Control – Code is stored and managed in a version control system like Git
  2. Build – The application is compiled and dependencies are installed. Tools like Maven, Gradle, or Docker are commonly used
  3. Automated Testing – Unit, integration, and security tests ensure the code is stable before deployment
  4. Artifact Management – Build artifacts (executables, images, or packages) are stored using Nexus, Artifactory, or Docker Registry
  5. Deployment (CI/CD) – The tested application is deployed to staging or production using tools like Jenkins, GitHub Actions, or ArgoCD
  6. Monitoring & Feedback – Performance and error tracking are done using Prometheus, Grafana, or ELK Stack to ensure reliability

Why it matters

A DevOps pipeline is the backbone of automation in modern software development. Interviewers ask this to see if you understand the key steps in delivering software efficiently.

For example

A company using CI/CD can push a code change to GitHub, triggering an automated build, testing, and deployment process.

This allows them to release new features multiple times a day without manual approval, improving software agility.

#12. How does Docker work, and why is it useful in DevOps?

Docker is a containerization platform that allows applications and their dependencies to be packaged into lightweight, portable containers.

These containers run consistently across different environments, eliminating compatibility issues between development, testing, and production.

How Docker works:

  1. Docker Image – A blueprint of a container that includes the application, libraries, and dependencies
  2. Docker Container – A running instance of a Docker image, isolated from the host system
  3. Dockerfile – A script that defines how to build a Docker image
  4. Docker Compose – A tool for managing multi-container applications using a YAML configuration file

Why Docker is useful in DevOps:

  • Portability – Containers run the same way on any system, reducing "it works on my machine" issues
  • Isolation – Applications and their dependencies are packaged together, avoiding conflicts
  • Scalability – Containers can be easily replicated and deployed using orchestration tools like Kubernetes
  • Fast Deployment – Containers start in seconds, making CI/CD pipelines faster and more efficient

Why it matters

Docker is a core DevOps tool because it enables consistent, scalable, and rapid application deployment. Interviewers ask this to see if you understand how containers improve software delivery.

For example

A development team using Docker can package their application into a container and deploy the same container in AWS, Azure, or Google Cloud without worrying about environment differences.

This ensures a consistent and error-free deployment process.

#13. What are Kubernetes pods, deployments, and services?

Kubernetes (K8s) is a container orchestration platform that manages the deployment, scaling, and operation of containerized applications.

Within Kubernetes, pods, deployments, and services are fundamental components for running applications efficiently.

Key Kubernetes components:

  • Pod – The smallest deployable unit in Kubernetes. A pod can run one or more containers that share storage, networking, and configurations
  • Deployment – A Kubernetes object that manages the desired state of pods. It ensures high availability, self-healing, and scaling by automatically restarting failed pods and distributing them across nodes
  • Service – A stable networking abstraction that exposes a set of pods to external traffic or other internal services. It enables communication between pods and external users

Why it matters

Interviewers ask this question to test your knowledge of Kubernetes architecture and how it enables scalable, resilient applications.

Understanding pods, deployments, and services is essential for deploying and managing microservices in Kubernetes.

For example

A web application running on Kubernetes may have:

  1. A Deployment managing multiple pods running the app’s containers
  2. A Service exposing the app externally via a LoadBalancer or Ingress
  3. Autoscaling enabled to handle increased traffic by launching additional pods automatically.

#14. What is a configuration management tool, and how does it help in DevOps?

A configuration management tool automates the process of deploying, managing, and maintaining infrastructure configurations across servers, ensuring consistency and reducing manual work.

These tools define infrastructure as code to ensure systems are repeatable and scalable.

Common configuration management tools:

  • Ansible – Agentless, uses YAML playbooks to configure servers and deploy applications
  • Puppet – Uses a declarative approach to automate infrastructure and enforce configuration policies
  • Chef – Uses "recipes" to define system configurations in Ruby DSL

How these tools help in DevOps:

  • Consistency – Ensures all servers and environments have the same configuration, reducing "it works on my machine" issues
  • Automation – Eliminates manual setup, reducing human errors and increasing efficiency
  • Scalability – Deploys and configures thousands of servers automatically
  • Self-healing infrastructure – Detects drift from the desired state and applies corrective actions

Why it matters

Interviewers ask this question to assess your understanding of infrastructure automation. Configuration management is essential in CI/CD pipelines, cloud environments, and large-scale deployments.

For example

A DevOps team managing hundreds of cloud servers can use Ansible to automatically apply security patches, configure networking, and install software — ensuring all machines are identical without manual intervention.

#15. What is the difference between Ansible, Puppet, and Chef?

Ansible, Puppet, and Chef are all configuration management tools used to automate infrastructure setup and maintenance, but they differ in architecture, ease of use, and automation approach.

Feature Ansible Puppet Chef
Language YAML (Ansible Playbooks) Puppet DSL (Declarative) Ruby DSL (Imperative)
Agent Required? No (Agentless) Yes (Requires agent) Yes (Requires agent)
Ease of Use Simple, easy to learn Moderate learning curve Complex, requires Ruby knowledge
Execution Push-based Pull-based Pull-based
Best for Quick automation, cloud infra Large-scale infrastructure Complex enterprise setups

Key differences explained:

  • Ansible is agentless and uses SSH or API calls to configure machines, making it easier to set up than Puppet or Chef
  • Puppet is declarative, meaning you define what the final state should be, and Puppet enforces it
  • Chef is imperative, meaning you define how the system should be configured, making it more flexible but also more complex

Why it matters

Interviewers ask this to see if you understand when to use each tool. Choosing the right tool depends on team expertise, infrastructure complexity, and automation needs.

For example

A startup using cloud-based infrastructure might prefer Ansible for its simplicity, while a large enterprise with thousands of servers might use Puppet to enforce strict configuration policies across multiple environments.

#16. What are the different types of testing in DevOps?

Testing in DevOps is critical for ensuring code quality, reliability, and security before deployment. Automated testing is integrated into the CI/CD pipeline to catch bugs early and prevent failures in production.

Common types of testing in DevOps:

  1. Unit Testing – Tests individual components of code for correctness
  2. Integration Testing – Ensures that different modules of an application work together
  3. Functional Testing – Verifies that the software meets business requirements
  4. Performance Testing – Evaluates how an application behaves under load
  5. Security Testing – Identifies vulnerabilities and ensures compliance with security standards
  6. Acceptance Testing – Validates whether the software meets customer expectations
  7. Chaos Testing – Intentionally injects failures to test system resilience and reliability

Why it matters

DevOps emphasizes shifting left, meaning testing happens earlier in the development cycle rather than waiting until production.

Interviewers ask this question to assess if you understand how testing improves software quality and stability in a DevOps workflow.

For example

A CI/CD pipeline may include unit tests at the build stage, integration tests before merging code, and security scans before deployment. This ensures that every change is tested at multiple levels, reducing the chances of production failures.

#17. What is Blue-Green Deployment, and how does it work?

Blue-Green Deployment is a release management strategy that minimizes downtime and reduces risk by maintaining two separate environments:

  • Blue Environment (Current Production) – The live environment serving users
  • Green Environment (New Release) – A copy of the production environment with the updated version of the application

How it works:

  1. The new version of the application is deployed to the Green environment while the Blue environment remains active.
  2. Once testing is complete, traffic is switched from Blue to Green, making the new version live.
  3. If any issues arise, traffic can be quickly rolled back to the Blue environment with minimal downtime.

Why it matters

Interviewers ask this question to test your understanding of deployment strategies that reduce downtime and deployment risk. Blue-Green Deployments allow zero-downtime updates, making them ideal for high-availability applications.

For example

An e-commerce website implementing a new feature can deploy it in the Green environment while users continue to browse the Blue (live) environment. After verifying the update, traffic is redirected to Green, ensuring a seamless transition without affecting customers.

#18. What is monitoring in DevOps, and why is it important?

Monitoring in DevOps is the practice of continuously tracking system performance, availability, and security to detect issues before they impact users. It involves collecting metrics, logs, and alerts to gain visibility into applications, infrastructure, and networks.

Types of monitoring in DevOps:

  • Infrastructure Monitoring – Tracks CPU, memory, disk usage, and server health
  • Application Performance Monitoring (APM) – Measures response times, error rates, and request latency
  • Log Monitoring – Aggregates and analyzes logs from different services for troubleshooting
  • Security Monitoring – Detects vulnerabilities, unauthorized access, and compliance violations

Popular monitoring tools:

  • Prometheus + Grafana – Used for real-time metrics visualization
  • ELK Stack (Elasticsearch, Logstash, Kibana) – For centralized log analysis
  • Datadog, New Relic, Splunk – Cloud-based monitoring solutions

Why it matters

Monitoring is crucial for proactive issue detection and system reliability. Interviewers ask this to see if you understand how DevOps teams ensure uptime and performance.

For example

A DevOps team running Kubernetes can use Prometheus to track CPU usage and Grafana dashboards to visualize traffic spikes, allowing them to scale resources before performance issues affect users.

#19. How do you handle secrets management in DevOps?

Secrets management in DevOps refers to securely storing, accessing, and managing sensitive data such as API keys, passwords, database credentials, and encryption keys.

Since DevOps relies heavily on automation and CI/CD, it’s crucial to ensure that secrets are not hardcoded in code repositories or exposed in logs.

Best practices for secrets management:

  • Use a secrets management tool – Store secrets securely using tools like:
    • HashiCorp Vault – Manages and encrypts secrets dynamically
    • AWS Secrets Manager / Azure Key Vault – Cloud-based solutions for storing and retrieving secrets securely
    • Kubernetes Secrets – Stores sensitive data in Kubernetes clusters securely
  • Environment Variables – Load secrets dynamically at runtime rather than storing them in configuration files
  • Least Privilege Principle – Grant access only to services or users that need specific secrets
  • Avoid storing secrets in repositories – Use .gitignore to exclude sensitive files from Git and implement pre-commit hooks to prevent accidental commits

Why it matters

Interviewers ask this question to ensure you understand security best practices in DevOps. Poor secrets management can lead to data breaches, security vulnerabilities, and compliance failures.

For example

A DevOps team managing a multi-cloud environment can use HashiCorp Vault to generate dynamic, time-limited database credentials instead of hardcoding passwords, reducing the risk of credential leaks.

#20. What is observability in DevOps, and how does it differ from monitoring?

Observability in DevOps is the ability to understand and diagnose the internal state of a system based on the data it produces. It goes beyond traditional monitoring by providing deeper insights into why an issue occurred, not just detecting that something went wrong.

Difference between observability and monitoring

Feature Monitoring Observability
Purpose Detects known issues and alerts teams Helps diagnose unknown issues by analyzing system behavior
Data Sources Uses logs, metrics, and alerts Uses logs, metrics, traces, and context
Approach Reactive – detects failures after they happen Proactive – helps understand system behavior and prevent failures
Example Tools Prometheus, Nagios, Zabbix OpenTelemetry, Datadog, Honeycomb

Three key pillars of observability:

  1. Logs – Detailed records of system events
  2. Metrics – Quantitative data on system performance (CPU, memory, latency)
  3. Traces – End-to-end tracking of requests across distributed systems

Why it matters

Interviewers ask this to see if you understand modern DevOps practices for diagnosing complex systems, because while monitoring detects issues, observability helps teams debug and optimize applications more effectively.

For example

A microservices-based application may generate logs in ELK Stack, metrics in Prometheus, and distributed traces in OpenTelemetry.

Observability tools can then correlate this data to help DevOps teams identify slow services and bottlenecks before they impact users.

Advanced DevOps Interview Questions

#21. How does Kubernetes handle scaling and load balancing?

Kubernetes (K8s) provides built-in scaling and load balancing mechanisms to efficiently manage workloads based on traffic and resource demand.

How Kubernetes handles scaling:

  1. Horizontal Pod Autoscaler (HPA) – Automatically increases or decreases the number of pods based on CPU, memory, or custom metrics
  2. Vertical Pod Autoscaler (VPA) – Adjusts the resource limits (CPU/RAM) of existing pods dynamically
  3. Cluster Autoscaler – Adds or removes nodes in a Kubernetes cluster when there are insufficient resources

How Kubernetes handles load balancing:

  • Service Load Balancing – Kubernetes Services distribute traffic among healthy pods within a deployment
  • Ingress Controller – Routes external traffic to different services based on hostname or URL path
  • External Load Balancers – Integrates with cloud providers (AWS, GCP, Azure) to create external-facing load balancers

Why it matters

Scalability and load balancing are critical for high-availability applications. Interviewers ask this to see if you understand how Kubernetes ensures reliable performance under varying workloads.

For example

An e-commerce platform experiencing traffic spikes on Black Friday can use HPA to auto-scale pods and Ingress to route traffic efficiently, ensuring zero downtime and optimal performance.

#22. What are the differences between monolithic, microservices, and serverless architectures?

Software architectures evolve based on scalability, flexibility, and operational requirements. The three most common architectures in DevOps are monolithic, microservices, and serverless.

Monolithic Architecture

  • A single, tightly coupled application where all components (UI, business logic, database) run as one unit
  • Simple to develop but hard to scale and deploy independently

Microservices Architecture

  • The application is broken down into small, independent services, each handling a specific function
  • Easier to scale, deploy, and update individual services without affecting the entire system.
  • Often deployed using containers and Kubernetes

Serverless Architecture

  • Code runs in event-driven functions that scale automatically (e.g., AWS Lambda, Azure Functions)
  • No need to manage infrastructure—cloud provider handles provisioning and scaling
  • Best for highly variable workloads and reducing operational overhead

Why it matters

Different applications require different architectures based on scale, complexity, and cost. Interviewers ask this to see if you can choose the right architecture for a given use case.

For example

A legacy banking system might use a monolithic approach, while a real-time streaming service like Netflix would rely on microservices, and a data-processing workflow may be best suited for serverless computing.

#23. What is GitOps, and how does it relate to DevOps?

GitOps is a DevOps practice that uses Git as the single source of truth for infrastructure and application deployments. It applies version control, automation, and CI/CD principles to infrastructure management, ensuring consistency and reliability.

How GitOps works:

  1. Declarative Infrastructure – Infrastructure is defined using Infrastructure as Code (IaC) tools like Terraform or Kubernetes manifests
  2. Git as the Source of Truth – The desired state of the system is stored in a Git repository
  3. Automated Syncing – A GitOps tool (e.g., ArgoCD, Flux) continuously monitors the repository and applies changes automatically
  4. Rollback & Auditing – Every infrastructure change is version-controlled, allowing easy rollbacks and auditing

Why it matters

Interviewers ask this to assess your understanding of modern infrastructure automation practices. GitOps brings consistency, automation, and security to DevOps workflows.

For example

A Kubernetes cluster using GitOps with ArgoCD can automatically apply changes to deployments when updates are pushed to the Git repository, ensuring a fully automated, auditable deployment process.

#24. What are the best practices for securing a DevOps pipeline?

Security in DevOps (often called DevSecOps) ensures that security is integrated throughout the software development lifecycle (SDLC) rather than being an afterthought.

Best practices for securing a DevOps pipeline:

  1. Use Secrets Management – Store sensitive credentials in HashiCorp Vault, AWS Secrets Manager, or Kubernetes Secrets, never in code
  2. Implement Role-Based Access Control (RBAC) – Restrict permissions using least privilege access to CI/CD tools and cloud resources
  3. Enable Code Scanning & Dependency Checks – Use SonarQube, Snyk, or OWASP Dependency-Check to detect vulnerabilities in code and dependencies
  4. Automate Security Testing – Integrate Static (SAST), Dynamic (DAST), and Infrastructure (IAST) security testing into CI/CD pipelines
  5. Sign and Verify Artifacts – Use Sigstore or Cosign to sign and verify container images before deployment
  6. Monitor and Audit Logs – Use SIEM tools like Splunk, ELK Stack, or Datadog to track pipeline activity and detect suspicious behavior

Why it matters

Interviewers ask this to test whether you understand how to integrate security into DevOps. A secure pipeline prevents data leaks, unauthorized access, and software supply chain attacks.

For example

A team deploying containers in AWS EKS can enforce image signing policies, use AWS Secrets Manager for credentials, and integrate Snyk for vulnerability scanning—ensuring a secure, automated CI/CD workflow.

#25. How do you optimize performance in a cloud-based DevOps environment?

Optimizing performance in a cloud-based DevOps environment involves improving efficiency, scalability, and cost-effectiveness while ensuring high availability.

Best practices for cloud performance optimization:

  1. Use Autoscaling – Configure horizontal and vertical scaling to dynamically adjust resources based on demand (e.g., AWS Auto Scaling, Kubernetes HPA)
  2. Optimize CI/CD Pipelines – Reduce build times using parallel execution, caching, and artifact reuse to speed up deployments
  3. Leverage Serverless & Containerization – Minimize resource waste by using serverless functions (AWS Lambda, Azure Functions) or lightweight containers instead of VMs
  4. Implement Caching Strategies – Use CDNs (CloudFront, Akamai), database caching (Redis, Memcached) to reduce latency
  5. Monitor & Optimize Resource Utilization – Use Prometheus, CloudWatch, Datadog to identify underutilized instances and adjust capacity
  6. Use Infrastructure as Code (IaC) – Automate provisioning with Terraform, CloudFormation to avoid over-provisioning and ensure consistency

Why it matters

Interviewers ask this to see if you can design cost-effective, high-performance cloud architectures that scale efficiently while avoiding unnecessary resource consumption.

For example

A media streaming service can use Kubernetes autoscaling, CDNs for content caching, and AWS Spot Instances to handle high traffic loads cost-effectively without over-provisioning infrastructure.

#26. What is Chaos Engineering, and how does it improve system reliability?

Chaos Engineering is the practice of intentionally injecting failures into a system to test its resilience, stability, and fault tolerance under real-world conditions. It helps teams identify weaknesses before they cause outages in production.

How Chaos Engineering works:

  1. Define a steady state – Establish normal system behavior (e.g., API response time, server health)
  2. Introduce controlled failures – Simulate failures like server crashes, network latency, or database outages
  3. Observe system behavior – Monitor how the system reacts and whether it self-recovers
  4. Improve system resilience – Use insights to fix vulnerabilities and implement auto-recovery mechanisms

Popular Chaos Engineering tools:

  • Chaos Monkey – Randomly terminates cloud instances to test fault tolerance
  • Gremlin – Injects controlled failures (CPU spikes, network delays, etc)
  • LitmusChaos – Kubernetes-native chaos testing tool

Why it matters

Interviewers ask this to see if you understand how to proactively test system reliability. Chaos Engineering is widely used in DevOps to ensure high availability and prevent unexpected failures.

For example

A banking platform might use Gremlin to simulate a database failure and test whether failover mechanisms correctly redirect traffic to a backup database, ensuring zero downtime.

#27. What are Site Reliability Engineering (SRE) principles, and how do they relate to DevOps?

Site Reliability Engineering (SRE) is a discipline that applies software engineering principles to IT operations to improve system reliability, scalability, and efficiency. It was pioneered by Google to bridge the gap between development and operations, similar to DevOps but with a focus on system reliability.

Key SRE principles:

  1. Service Level Objectives (SLOs) – Define performance targets (e.g., 99.9% uptime)
  2. Service Level Agreements (SLAs) – Commitments to customers based on SLOs
  3. Error Budgets – Allowable downtime before action is taken (trade-off between reliability and feature velocity)
  4. Automation & Toil Reduction – Minimize repetitive manual work by automating deployments, monitoring, and incident response
  5. Blameless Postmortems – Encourage learning from failures without blaming individuals, fostering continuous improvement

How SRE relates to DevOps:

  • SRE focuses on reliability, while DevOps focuses on agility
  • Both emphasize automation, CI/CD, and monitoring, but SRE prioritizes system stability and incident response
  • Many companies merge SRE and DevOps roles, integrating reliability-focused practices into DevOps workflows

Why it matters

Interviewers ask this to test your understanding of operational excellence in DevOps. SRE principles help balance innovation with system reliability, ensuring that frequent deployments don’t compromise uptime.

For example

A cloud provider might define an SLO of 99.99% uptime, use error budgets to determine when to slow feature releases, and automate incident response using AI-powered monitoring tools like Datadog or PagerDuty.

#28. How do you handle stateful applications in Kubernetes?

By default, Kubernetes is designed for stateless applications, where instances can be freely replaced without worrying about persistent data. However, many enterprise applications require stateful workloads, such as databases, message queues, and distributed storage systems.

Best practices for handling stateful applications in Kubernetes:

Use StatefulSets

Unlike Deployments, StatefulSets ensure:

  • Pods have stable, unique network identities
  • Persistent storage remains associated with each pod even after restarts

Persistent Volumes (PV) & Persistent Volume Claims (PVC)

Allow pods to retain data across restarts by connecting to external storage providers (AWS EBS, Azure Disks, Google Persistent Disks, Ceph)

Headless Services

Enable direct pod-to-pod communication within a StatefulSet by providing stable DNS names for stateful workloads

Database Operators

Use Kubernetes operators (e.g., PostgreSQL Operator, MySQL Operator) to simplify automated backups, replication, and failover

Replication & High Availability

Deploy stateful applications with multi-zone replication and automated failover to prevent data loss during outages

Why it matters

Interviewers ask this question to assess whether you understand how to run databases and other stateful applications in Kubernetes without data loss or downtime.

For example

A financial application running on Kubernetes may use a StatefulSet for PostgreSQL, persistent volumes for database storage, and an operator to automate replication and backup, ensuring high availability and fault tolerance.

#29. What are some common challenges in implementing DevOps, and how do you overcome them?

While DevOps improves software delivery and operations, its adoption comes with organizational, technical, and cultural challenges that teams must address.

Common DevOps challenges and solutions:

Resistance to Change

  • Challenge: Traditional IT and development teams may resist adopting new workflows
  • Solution: Promote a DevOps culture with training, leadership support, and gradual adoption

Siloed Teams & Poor Collaboration

  • Challenge: Dev and Ops teams working separately slow down deployments
  • Solution: Encourage cross-functional collaboration, use tools like Slack, Jira, and GitOps, and implement shared responsibilities

Security & Compliance Risks

  • Challenge: Faster deployments can introduce security vulnerabilities
  • Solution: Integrate DevSecOps, automate security scanning (SAST, DAST), and enforce role-based access control (RBAC)

Legacy Infrastructure & Technical Debt

  • Challenge: Older systems may not support automation or cloud-native workflows
  • Solution: Gradual modernization using containerization, microservices, and hybrid cloud strategies

CI/CD Pipeline Failures & Unstable Releases

  • Challenge: Poorly configured pipelines can cause deployment failures
  • Solution: Implement automated testing, rollback strategies, and canary deployments to catch issues early

Why it matters

Interviewers ask this to see if you understand real-world DevOps implementation challenges and how to solve them. Strong candidates don’t just know the tools—they know how to navigate obstacles.

For example

A large enterprise transitioning to DevOps might gradually containerize legacy applications, use GitOps for managing deployments, and conduct blameless postmortems to continuously improve its workflows.

#30. How do you implement disaster recovery and high availability in a DevOps environment?

Disaster recovery (DR) and high availability (HA) are critical strategies for ensuring business continuity and minimizing downtime in the event of system failures, cyberattacks, or natural disasters.

Key strategies for Disaster Recovery (DR) and High Availability (HA)

Multi-Region & Multi-AZ Deployments

  • Deploy workloads across multiple availability zones (AZs) or cloud regions to prevent failures from affecting the entire system

Automated Backups & Snapshots

  • Use automated database and file system backups (e.g., AWS Backup, Velero for Kubernetes) with versioning to enable quick recovery

Active-Active & Active-Passive Architectures

  • Active-Active: Traffic is distributed across multiple live instances (e.g., global load balancing)
  • Active-Passive: A standby instance takes over when the primary fails (e.g., failover databases)

Load Balancing & Auto Scaling

  • Use load balancers (e.g., AWS ALB, Nginx) and autoscaling (e.g., Kubernetes HPA, AWS Auto Scaling) to distribute traffic and prevent overloads

Infrastructure as Code (IaC) for Rapid Recovery

  • Use Terraform, CloudFormation, or Ansible to quickly reprovision infrastructure in case of a disaster

Incident Response & Chaos Engineering

  • Conduct disaster recovery drills and use Chaos Engineering tools like Gremlin to test system resilience before real failures occur

Why it matters

Interviewers ask this to assess whether you understand how to design resilient systems that can withstand failures while maintaining uptime. A strong answer should include both proactive (HA) and reactive (DR) strategies

For example

A global e-commerce platform can ensure high availability using multi-region AWS deployments, implement RDS automated backups, and use Kubernetes auto-healing to restart failed pods—ensuring zero downtime even in case of outages.

So what's next?

And there you have it — 30 of the most common DevOps interview questions and answers to help you prepare for your next job opportunity.

But remember, interviews aren’t just about reciting answers—they’re about demonstrating real understanding. DevOps is all about collaboration, automation, and problem-solving, so be ready to share your own experiences implementing these concepts in real-world scenarios.

If you’re still brushing up on key DevOps skills, consider diving deeper into CI/CD, Kubernetes, Infrastructure as Code (IaC), and cloud automation. The better you understand these concepts, the more confidently you'll be able to tackle both technical and scenario-based interview questions.

This way you’ll be able to share even more details and context, and show you really know what you’re talking about.

P.S.

How did you do? Did you nail all 30 questions? If so, it might be time to move from studying to actively interviewing!

Didn't get them all? Got tripped up on a few? Don't worry; I'm here to help.

Like I said earlier, if you find that you’re struggling with the questions in this guide, or perhaps feel that you could use some more training and want to build some more impressive projects for your portfolio, then check out my complete DevOps / Sysadmin Course:

learn devops

Not only do I cover the basics so you have a concrete foundation, but this course ensures that you’ll actually retain what you're learning by letting you apply DevOps in real-world scenarios.

You get hands-on experience by configuring a Linux Server from scratch in the cloud, as well as quizzes and challenges at the end of each section.

Plus, once you join, you'll have the opportunity to ask questions in our private Discord community from me, other students and other working DevOps professionals, as well as access to every other course in our library!


If you join or not, I just want to wish you the best of luck with your interview. And if you are a member, let me know how it goes over in the DevOps channel!

More from Zero To Mastery

How to Become a DevOps Engineer & Get Hired in 2025 preview
Popular
How to Become a DevOps Engineer & Get Hired in 2025

Learn everything you need to know to become a DevOps Engineer, as well as how to get hired as one in 2025 with this step-by-step guide!

4 Tips To Keep Your Tech Skills Up To Date preview
Popular
4 Tips To Keep Your Tech Skills Up To Date

Tech moves at a crazy pace, and it's easy to be left behind. Here are 4 tried and tested tips to not only stay up to date but get ahead of the curve!

A Beginners Guide To Computer Networking preview
A Beginners Guide To Computer Networking

Are you a budding DevOps Engineer or Cybersecurity Analyst? Learn the basics of networking, including key concepts like network topologies, OSI model, and more.