DevOps Interview Questions And Answers for Freshers, Intermediate and Experienced
In today’s fast-paced and highly competitive software development landscape, DevOps has emerged as a critical methodology for organizations aiming to streamline their operations and deliver high-quality software at an accelerated pace. As a result, DevOps engineers have become in-demand professionals who possess a unique skill set combining development, operations, and automation expertise.
If you’re preparing for a DevOps interview, it’s essential to be well-versed in a range of topics and also to get trained by pursuing DevOps online course from CRS Info Solutions. In this blog post, we’ll explore a wide array of DevOps interview questions, categorized according to the level of expertise.
What is DevOps?
Before diving into the interview questions, let’s start with the fundamentals. DevOps is a collaborative approach that combines software development (Dev) and IT operations (Ops) to foster a culture of continuous integration, continuous delivery, and continuous deployment. It emphasizes automation, communication, collaboration, and measurement to enable organizations to deliver software more efficiently and reliably.
An integral part of DevOps is the utilization of various tools that facilitate automation and streamline the software development lifecycle. Some popular DevOps tools include Jenkins, Ansible, Docker, Kubernetes, Git, and many more. It’s crucial to familiarize yourself with these tools and understand how they contribute to the DevOps ecosystem.
DevOps Interview Questions for Freshers
For candidates new to the DevOps field, here are some essential interview questions:
Q 1. Who is a DevOps engineer?
A DevOps engineer is a professional responsible for bridging the gap between development and operations teams. They possess a diverse skill set, including coding, scripting, infrastructure management, and automation expertise.
Q 2. Why has DevOps become famous?
DevOps has gained popularity due to its ability to enhance collaboration, accelerate software delivery, and improve overall operational efficiency. By breaking down silos and promoting cross-functional teams, DevOps helps organizations achieve faster time-to-market and higher customer satisfaction.
Q 3. What is the use of SSH?
SSH (Secure Shell) is a network protocol used for secure remote access to systems. In the context of DevOps, SSH is often used for secure communication between servers and for executing commands remotely.
Q 4. What is configuration management?
Configuration management is the process of managing and maintaining the consistency of system configurations across different environments. It involves defining and tracking the state of infrastructure and applications, enabling reproducibility and scalability.
Q 5. What is the importance of having configuration management in DevOps?
Configuration management is crucial in DevOps as it allows for standardized and automated provisioning of infrastructure and applications. It ensures consistency, reduces errors, and enables efficient scaling and recovery.
Q 6. What does CAMS stand for in DevOps?
CAMS stands for Culture, Automation, Measurement, and Sharing. It represents the core principles of DevOps, emphasizing the importance of fostering a collaborative culture, automating processes, measuring performance, and sharing knowledge.
Q 7. What is Continuous Integration?
Continuous Integration is a practice where developers regularly merge their code changes into a shared repository. The merged code is then automatically built, tested, and verified to detect integration issues early in the development cycle.
Q 8. Why is Continuous Integration needed?
Continuous Integration helps identify and address integration problems early, promotes faster feedback loops, and ensures that the codebase remains in a releasable state. It minimizes the risks associated with integrating code from multiple developers and facilitates smoother collaboration.
Q 9. What is Continuous Testing (CT)?
Continuous Testing is the practice of executing automated tests throughout the software development lifecycle to provide feedback on the quality and functionality of the code. It involves running tests continuously, validating changes made to the codebase, and ensuring that all components work together as expected.
Q 10. What are the three important DevOps KPIs?
Key Performance Indicators (KPIs) are metrics used to measure the success and effectiveness of DevOps practices. Three important DevOps KPIs include:
- Deployment Frequency: This measures how frequently new features, bug fixes, or updates are deployed to production.
- Lead Time: It refers to the time taken from code commit to the deployment of a feature or changes into production.
- Mean Time to Recover (MTTR): MTTR measures the average time required to recover from a failure or incident and restore normal system functionality.
Intermediate Interview Questions
For candidates with some experience in the DevOps field, here are some intermediate-level interview questions:
Q 11. Explain the different phases in the DevOps methodology.
DevOps involves several phases, including planning, coding, building, testing, deployment, operation, and monitoring. Each phase plays a crucial role in the software development lifecycle, ensuring seamless collaboration and efficient delivery.
Q 12. How is DevOps different from Agile Methodology?
While both DevOps and Agile focus on collaboration and iterative development, DevOps primarily deals with the integration of development and operations, emphasizing automation and continuous delivery. Agile, on the other hand, focuses on iterative development and adaptive planning.
Q 13. Differentiate between Continuous Deployment and Continuous Delivery.
Continuous Deployment refers to automatically deploying code changes to production without manual intervention, assuming all tests and quality checks pass. Continuous Delivery, on the other hand, involves having code changes in a state where they could be deployed to production at any time, but the actual deployment decision is made manually.
Q 14. What can you say about the antipatterns of DevOps?
Antipatterns in DevOps refer to common pitfalls or counterproductive practices that hinder the successful implementation of DevOps principles. These can include a lack of collaboration, siloed teams, insufficient automation, and resistance to change. Understanding antipatterns helps organizations identify areas for improvement and implement effective DevOps strategies.
Q 15. Can you tell me something about Memcached?
Memcached is a popular open-source, distributed caching system used to improve the performance and scalability of web applications. It stores frequently accessed data in memory, reducing the load on backend systems and improving response times.
Q 16. What are the various branching strategies used in the version control system?
Common branching strategies include GitFlow, Feature Branching, and Trunk-Based Development. These strategies define how developers collaborate, manage code changes, and handle release cycles within a version control system.
Q 17. Can you list down certain KPIs used for gauging the success of DevOps?
Some KPIs used to measure the success of DevOps implementations include deployment frequency, lead time, change failure rate, customer satisfaction, and system uptime. These metrics provide insights into the efficiency, quality, and customer-centricity of the DevOps processes.
Q 18. What is CBD in DevOps?
CBD stands for Container-Based Deployment. It refers to the practice of packaging applications and their dependencies into lightweight, portable containers, such as Docker containers. CBD enables consistent deployment across different environments and simplifies application scalability and management.
Q 19. What is Resilience Testing?
Resilience Testing, also known as Chaos Engineering, involves intentionally injecting failures or disruptions into a system to observe how it behaves and recovers. It helps identify vulnerabilities, strengthen system resilience, and improve overall system reliability in real-world scenarios.
Q 20. Can you differentiate between continuous testing and automation testing?
Continuous testing is an integral part of the DevOps process, where automated tests are executed continuously throughout the software development lifecycle. It ensures that code changes are validated promptly and effectively. Automation testing, on the other hand, refers to the practice of using tools and scripts to automate the execution of tests, enabling faster and more reliable testing processes.
Q 21. Can you say something about the DevOps pipeline?
The DevOps pipeline, also known as the CI/CD pipeline, is a series of automated steps and stages that code changes go through, from development to production deployment. It typically includes building, testing, deploying, and monitoring stages, all orchestrated to ensure a seamless and efficient software delivery process.
Q 22. Tell me something about Ansible’s work in DevOps.
Ansible is an open-source automation tool that plays a vital role in DevOps. It enables the automation of configuration management, application deployment, and infrastructure provisioning tasks. With Ansible, developers and operations teams can define infrastructure as code and manage complex systems more effectively.
Q 23. How does Ansible work?
Ansible operates by connecting to remote machines through SSH and executing tasks defined in YAML-based playbooks. It uses a push-based model, where the control node pushes the necessary configurations and commands to the target nodes, enabling seamless automation and orchestration of infrastructure.
Q 24. What role does AWS play in DevOps?
AWS (Amazon Web Services) offers a wide range of services and tools that support DevOps practices. It provides scalable and on-demand infrastructure resources, such as Amazon EC2 and Amazon S3, along with services like AWS CodePipeline and AWS CodeDeploy for building and deploying applications. AWS also offers managed services for containerization, serverless computing, and monitoring, enabling organizations to implement robust DevOps pipelines.
Q 25. What can be a preparatory approach for developing a project using the DevOps methodology?
When starting a project with DevOps, a preparatory approach involves several key steps. These include setting up version control, defining the CI/CD pipeline, establishing infrastructure-as-code practices, implementing automation frameworks, defining testing strategies, and fostering a collaborative culture. By taking these steps, teams can lay a solid foundation for a successful DevOps implementation.
DevOps Interview Questions for Experienced
For candidates with significant experience in the DevOps field, here are some advanced-level interview questions:
Q 26. Can you explain the “Shift left to reduce failure” concept in DevOps?
The “Shift left” concept in DevOps emphasizes moving quality assurance and testing activities earlier in the development cycle. By incorporating testing and quality checks from the initial stages, such as code reviews and unit testing, organizations can detect and address issues earlier, reducing the chances of failures or defects in production.
Q 27. Do you know about post-mortem meetings in DevOps?
Post-mortem meetings, also known as blameless retrospectives, are an integral part of the DevOps culture. They involve a collaborative review of incidents, failures, or outages to identify the root causes, learn from them, and implement preventive measures. The goal is to foster a blame-free environment that encourages continuous improvement and learning.
Q 28. What is the concept behind sudo in Linux OS?
In Linux operating systems, “sudo” stands for “superuser do.” It allows authorized users to execute specific commands with elevated privileges. Sudo enables users to perform administrative tasks while maintaining security and control over the system.
Q 29. Can you explain the architecture of Jenkins?
Jenkins is an open-source automation server widely used in Dev Ops. Its architecture follows a master-slave model. The Jenkins master is responsible for managing the configuration, scheduling, and monitoring of jobs. The master communicates with multiple Jenkins slave nodes, which are responsible for executing the actual build and deployment tasks. The slaves can be distributed across different machines or environments, allowing for parallel and scalable execution of jobs.
Q 30. Can you explain the “infrastructure as code” (IaC) concept?
Infrastructure as Code (IaC) is a method that involves managing and provisioning infrastructure resources using machine-readable definition files. Instead of manually configuring servers and environments, IaC allows developers and operations teams to define infrastructure requirements using code. This approach brings automation, version control, and repeatability to infrastructure management, enabling faster and more reliable deployments.
Q 31. What is ‘Pair Programming’?
Pair Programming is an Agile software development technique where two programmers work together on the same codebase. One person acts as the “driver,” writing the code, while the other person serves as the “navigator,” providing guidance, reviewing the code, and suggesting improvements. Pair Programming promotes knowledge sharing, collaboration, and collective code ownership.
Q 32. What is the Blue/Green Deployment Pattern?
The Blue/Green Deployment Pattern is a release management strategy in which two identical production environments, referred to as “Blue” and “Green,” are set up. The current live version of the application runs in one environment, while the updated version is deployed in the other. Once the new version is tested and validated, traffic is switched from the old environment (Blue) to the new environment (Green), minimizing downtime and reducing the risk of impacting end-users.
Q 33. What is the Dogpile effect? How can it be prevented?
The Dogpile effect, also known as cache stampede, occurs when a cache expires, and multiple requests simultaneously hit the backend to regenerate the cache. This sudden spike in requests can overload the system and cause performance degradation. To prevent the Dogpile effect, techniques like cache locking or using adaptive expiration policies can be employed. Cache locking ensures that only one request regenerates the cache, while adaptive expiration policies stagger cache expiration to distribute the load evenly.
Q 34. What are the steps to be undertaken to configure a Git repository to run code sanity-checking tools before any commits? How do you prevent it from happening again if the sanity testing fails?
To configure a Git repository for code sanity checking before commits, you can set up a pre-commit hook. The pre-commit hook is a script that runs before each commit and performs sanity checks on the code. If the sanity testing fails, the hook prevents the commit from being executed, providing feedback to the developer.
To prevent the failure from happening again, developers can receive immediate feedback on the issues found during sanity testing. They can then address the issues, fix the code, and reattempt the commit. This iterative process ensures that code quality is maintained and improves over time.
Q 35. How can you ensure a script runs every time the repository gets new commits through git push?
Git hooks may be used to ensure that a script executes every time a repository receives new commits via git push. You can, for example, configure a post-receive hook to run after new commits have been received and placed in the repository. The post-receive hook may be used to run the script or workflow you desire, allowing you to conduct extra actions or processes on freshly received commits.
In conclusion, DevOps interviews often cover a wide range of topics, including the definition and benefits of DevOps, various tools and technologies, and key concepts like Continuous Integration, Continuous Deployment, and Infrastructure as Code. The interview questions discussed in this blog provide a comprehensive overview of DevOps interview questions for both freshers and experienced professionals. Understanding these questions and their answers can help you prepare effectively for your DevOps interview and showcase your knowledge and expertise in the field.