DevOps Interview Questions and Answers

DevOps stands for Development and Operations. It is a software engineering practice that focuses on bringing together the development team and the operations team for the purpose of automating the project at every stage. This approach helps in easily automating the project service management in order to aid the objectives at the operational level and improve the understanding of the technological stack used in the production environment.

This way of practice is related to agile methodology and it mainly focuses on team communication, resource management, and teamwork. The main benefits of following this structure are the speed of development and resolving the issues at the production environment level, the stability of applications, and the innovation involved behind it.

1. What is DevOps?

DevOps is a set of practices, tools, and a cultural philosophy that automates and integrates the processes between software development and IT teams. It emphasizes team empowerment, cross-team communication and collaboration, and technology automation.

DevOps can be defined as a combination of software development practices and tools used for increasing organizations’ ability while delivering applications, services, and more in close alignment with business objectives.

2. Why DevOps is Important?

DevOps is more about a set of processes that correlate to bring development teams and processes to support software development. The important reason behind the DevOps popularity is that it helps enterprises to build and enhance products at a quicker pace than traditional software development methods.

The major reasons to adopt DevOps are listed below:

• Faster innovations
• Shorter development cycles
• Reduced deployment failures
• Improved communication and collaboration
• More stable operating environments
• Increased efficiencies
• Reduced Costs and IT Headcount

3. What are the principles of DevOps?

The principles behind DevOps are:

• Continuous deployment
• Infrastructure as code
• Automation
• Monitoring
• Security

4. What are the prerequisites that are useful for DevOps implementation?

• Containers Understanding
• Understanding the DevOps Tools and Technologies
• Knowledge of Scripting Languages
• DevOps Training and Certification
• Knowledge of Automation Tools
• Testing
• Excellent Collaboration and Communication Skills
• Knowledge of Networking fundamentals
• Overall Computer Science Knowledge
• Knowledge of Cloud computing
• Knowledge of different OS

5. What are the best practices for DevOps implementation?

• Build a collaborative culture -> Code, Develop, Test, release and monitor
• Put customer satisfaction first
• Use agile project management
• Adopt continuous integration and delivery
• Monitor
• Switch to microservices

6. What are your roles and responsibilities as a DevOps engineer?

• Communication
• Experience with DevOps tools
• Project management
• Optimizing release cycles
• Coding knowledge
• Infrastructure knowledge
• Cloud platform integration
• Monitoring
• Configuration management
• Source code management
• Developing CI/CD pipelines
• Containerization
• Testing

7. Explain CI/CD Pipelines? What are the elements of CI/CD?

A CI/CD pipeline is a series of steps that must be performed in order to deliver a new version of the software. Continuous integration/continuous delivery (CI/CD) pipelines are a practice focused on improving software delivery using either a DevOps or site reliability engineering (SRE) approach.

Elements of a CI/CD pipeline:

Build > Test > Release > Deploy

8. What are the key components of DevOps?

• Continuous development
• Continuous integration
• Continuous testing
• Continuous deployment
• Continuous monitoring
• Continuous feedback
• Continuous operations

9. What is Continuous Integration? How to implement it?

Continuous integration (CI) is the practice of automating the integration of code changes from multiple contributors into a single software project. It’s a primary DevOps best practice, allowing developers to frequently merge code changes into a central repository where builds and tests are then run. Automated tools are used to assert the new code’s correctness before integration. Tool: Bitbucket Pipelines, Jenkins, Atlassian Bamboo.

Based on the above flow, we can have a brief overview of the CI process.

• Developers regularly check out code into their local workspaces and work on the features assigned to them.
• Once they are done working on it, the code is committed and pushed to the remote shared repository which is handled by making use of effective version control tools like git.
• The CI server keeps track of the changes done to the shared repository and it pulls the changes as soon as it detects them.
• The CI server then triggers the build of the code and runs unit and integration test cases if set up.
• The team is informed of the build results. In case of the build failure, the team has to work on fixing the issue as early as possible, and then the process repeats.

How to implement CI:

• Create a centralized repository.
• Automate build and test.
• Upload changes every few hours.
• Perfect your test environment.
• Automate deployment.

10. What is Continuous Delivery? How to implement it?

Continuous Delivery is the ability to get changes of all types: including new features, configuration changes, bug fixes, and experiments – into production, or into the hands of users, safely and quickly in a sustainable way.

How to implement Continuous Delivery:

• Pick a Small, Manageable Project to Start
• Define a Process
• Ensure a Blameless Culture
• Set Metrics and Measure Your Success
• Adopt Configuration as Code
• Adopt Configuration as Code

11. What is Continuous Testing? How to implement it?

Continuous testing (CT) is a software development process in which applications are tested continuously throughout the entire software development life cycle (SDLC). The goal of CT is to evaluate software quality across the SDLC, providing critical feedback earlier and enabling higher-quality and faster deliveries.

How to implement Continuous Testing:

• Adopt More Test Automation
• Tool Integration
• Tracking Metrics
• Leverage Containerization
• Keep Communication Transparent
• Save Time with Headless Execution
• Multi-layer Tests
• Integrate Performance Testing into Delivery Cycle

12. What is Continuous Monitoring? How to implement it?

Continuous monitoring is a technology and process that IT organizations may implement to enable rapid detection of compliance issues and security risks within the IT infrastructure. Continuous monitoring is one of the most important tools available for enterprise IT organizations, empowering SecOps teams with real-time information from throughout public and hybrid cloud environments and supporting critical security processes like threat intelligence, forensics, root cause analysis, and incident response.

How to implement Continuous Monitoring:

• Enable web applications and services monitoring for complete observation.
• Monitor all relevant components of infrastructure like servers, security, networks, performance, etc.
• Maintain separate instances for monitoring multiple deployment environments in order to maintain data relevancy across all platforms, be it apps or infrastructure.
• Prepare workbooks with metric charts, and log queries of guides for troubleshooting basic problems.
• Configure actionable alerts for any possible issues or failures.

13. Explain your approach when a project needs to implement DevOps?

• Prepare for a cultural shift
• Create a continuous integration, continuous delivery platform
• Create a continuous testing environment
• Establish a continuous deployment system
• Make use of blue/green deployment
• Continuously monitor performance
  • Development Cycles > Deployments > Vulnerabilities > Server health > Application performance

14. What are the fundamental differences between DevOps & Agile?

The differences between the two are listed in the table below.

Features	DevOps	Agile
Agility	Agility is both Development & Operations	Agility in only Development
Processes/ Practices	Involves processes such as CI, CD, CT, etc.	Involves practices such as Agile Scrum, Agile Kanban, etc.
Key Focus Area	Timeliness & quality have equal priority	Timeliness is the main priority
Release Cycles/ Development Sprints	Smaller release cycles with immediate feedback	Smaller release cycles
Source of Feedback	Feedback is from self (Monitoring tools)	Feedback is from customers
Scope of Work	Agility & need for Automation	Agility only

15. What are the top 10 DevOps tools that are in demand in today’s market?

• Version Control Tool: Git (GitLab, GitHub, Bitbucket)
• Build Tool: Maven
• Continuous Integration Tool: Jenkins, Hudson, CircleCI
• Configuration Management Tool: Chef, TeamCity, Bamboo, Ansible, Puppet
• Container Platforms: Docker, Kubernetes
• Software tool: Terraform.
• Database: Oracle, MySQL.
• Monitoring: Zabbix, Nagios, graffana
• Communication and Collaboration: Slack
• Testing Tool: Selenium
• IT Ticketing: Servicenow

16. Why DevOps has become famous?

These days, the market window of products has reduced drastically. We see new products almost daily. This provides a myriad of choices to consumers but it comes at a cost of heavy competition in the market. Organizations cant afford to release big features after a gap. They tend to ship off small features as releases to the customers at regular intervals so that their products don’t get lost in this sea of competition.

Customer satisfaction is now a motto to the organizations which has also become the goal of any product for its success. In order to achieve this, companies need to do the below things:

• Frequent feature deployments
• Reduce time between bug fixes
• Reduce failure rate of releases
• Quicker recovery time in case of release failures.
• In order to achieve the above points and thereby achieve seamless product delivery, DevOps culture acts as a very useful tool. Due to these advantages, multi-national companies like Amazon and Google have adopted the methodology which has resulted in their increased performance.

17. Explain the different phases in DevOps methodology.

DevOps mainly has 6 phases and they are:

Planning:

This is the first phase of a DevOps lifecycle that involves a thorough understanding of the project to ultimately develop the best product. When done properly, this phase gives various inputs required for the development and operations phases. This phase also helps the organization to gain clarity regarding the project development and management process.

Tools like Google Apps, Asana, Microsoft teams, etc are used for this purpose.

Development:

The planning phase is followed by the Development phase where the project is built by developing system infrastructure, developing features by writing codes, and then defining test cases and the automation process. Developers store their codes in a code manager called remote repository which aids in team collaboration by allowing view, modification, and versioning of the code.

Tools like git, IDEs like the eclipse, IntelliJ, and technological stacks like Node, Java, etc are used.

Continuous Integration (CI):

This phase allows for the automation of code validation, build, and testing. This ensures that the changes are made properly without development environment errors and also allows the identification of errors at an initial stage.

Tools like Jenkins, circleCI, etc are used here.

Deployment:

DevOps aids in the deployment automation process by making use of tools and scripts which has the final goal of automating the process by means of feature activation. Here, cloud services can be used as a force that assists in upgrade from finite infrastructure management to cost-optimized management with the potential to infinite resources.

Tools like Microsoft Azure, Amazon Web Services, Heroku, etc are used.

Operations:

This phase usually occurs throughout the lifecycle of the product/software due to the dynamic infrastructural changes. This provides the team with opportunities for increasing the availability, scalability, and effective transformation of the product.

Tools like Loggly, BlueJeans, Appdynamics, etc are used commonly in this phase.

Monitoring:

Monitoring is a permanent phase of the DevOps methodology. This phase is used for monitoring and analyzing information to know the status of software applications.

Tools like Nagios, Splunk, etc are commonly used.

18. Differentiate between Continuous Deployment and Continuous Delivery?

The main difference between Continuous Deployment and Continuous Delivery are given below:

Continuous Deployment	Continuous Delivery
The deployment to the production environment is fully automated and does not require manual/ human intervention.	In this process, some amount of manual intervention with the manager’s approval is needed for deployment to a production environment.
Here, the application is run by following the automated set of instructions, and no approvals are needed.	Here, the working of the application depends on the decision of the team.

19. What can you say about the antipatterns of DevOps?

A pattern is something that is most commonly followed by large masses of entities. If a pattern is adopted by an organization just because it is being followed by others without gauging the requirements of the organization, then it becomes an anti-pattern. Similarly, there are multiple myths surrounding DevOps which can contribute to antipatterns, they are:

• DevOps is a process and not a culture.
• DevOps is nothing but Agile.
• There should be a separate DevOps group.
• DevOps solves every problem.
• DevOps equates to developers running a production environment.
• DevOps follows Development-driven management
• DevOps does not focus much on development.
• As we are a unique organization, we don’t follow the masses and hence we won’t implement DevOps.
• We don’t have the right set of people, hence we cant implement a DevOps culture.

20. How does AWS contribute to DevOps?

AWS stands for Amazon Web Services and it is a well-known cloud provider. AWS helps DevOps by providing the below benefits:

• Flexible Resources: AWS provides ready-to-use flexible resources for usage.
• Scaling: Thousands of machines can be deployed on AWS by making use of unlimited storage and computation power.
• Automation: Lots of tasks can be automated by using various services provided by AWS.
• Security: AWS is secure and using its various security options provided under the hood of Identity and Access Management (IAM), the application deployments and builds can be secured.

21. What can be a preparatory approach for developing a project using the DevOps methodology?

The project can be developed by following the below stages by making use of DevOps:

• Stage 1: Plan: Plan and come up with a roadmap for implementation by performing a thorough assessment of the already existing processes to identify the areas of improvement and the blind spots.
• Stage 2: PoC: Come up with a proof of concept (POC) just to get an idea regarding the complexities involved. Once the PoC is approved, the actual implementation work of the project would start.
• Stage 3: Follow DevOps: Once the project is ready for implementation, actual DevOps culture could be followed by making use of its phases like version control, continuous integration, continuous testing, continuous deployment, continuous delivery, and continuous monitoring.

22. What is VCS?

Version control systems are a kind of software tool which reports the changes in the code and integrates these changes with the existing code. As the developer makes changes in the code frequently, these types of tools are helpful in integrating the new code smoothly without disturbing the work of other team members. Along with integration, it will test the new code so that we can avoid the code leading to bugs)

23. What are the types of Version Control Systems?

Primarily there are three types of Version control systems they are:

• Local Version Control Systems
• Centralized Version Control Systems
• Distributed Version Control Systems

24. What are the benefits of version control?

The primary benefits you can expect from a version control system are the following:

• Complete long-term change history of every file is available.
• All the past versions and variants are kept independent from each other inside the VCS through branching, and whenever required, you can merge them back together with the file’s content to verify the changes. 

25. What is Git?

Git is a distributed version control system particularly used for recording the changes in the source code during software development. It manages a set of files or a project that change over time. It stores the information in a data structure called the repository.

Let’s understand the importance of Git through its benefits to organizations:

• Feature branch workflow
• Distributed development
• Pull requests
• Data redundancy and replication
• High availability
• Superior disk utilization and network performance
• Collaboration friendly