DevOps is one of the hottest trends in technology right now, although it is much more exciting and powerful. It is a relationship between the development and operations team to deliver a product faster and efficiently.
For the past 2-3 years, DevOps enthusiasts have had an insignificant increase in job listings. Many multinational companies, like Microsoft, Google, Facebook, and Amazon, frequently have multiple open positions for DevOps. However, cracking the DevOps interview is not a piece of cake. It requires preparation and dedication.
To help you out, we have acquired the Top DevOps Interview Questions and Answers, and they will definitely help you progress forward in DevOps development.
This blog covers the following levels of AWS Interview Questions.
- DevOps Interview Questions – Beginner
- DevOps Interview Questions – Intermediate
- DevOps Interview Questions – Advanced
Beginners Level
DevOps Interview Questions
Q1. What are the differences between DevOps & Agile?
Q2. What is the need for DevOps?
It breaks down communication barriers between development and IT operations teams; the core value of DevOps is to achieve customer satisfaction and deliver its content faster.
The practice of DevOps helps to achieve faster & more secure Delivery of business value to any organization. This value takes the form of more frequent product releases, features, or updates. It can involve how rapidly a product release or new feature gets into the client’s hands. Or, it focuses on how efficiently an issue or bug is identified and then resolved and re-released.
Devops also help to achieve the following parameters:
- Increase deployment frequency
- The lower failure rate of new releases product
- Shortened lead time between fixes
- Faster mean time to recovery in the event of new release crashing
Q3. What is Continous Integration & Continous Deployment
Continuous Integration is a coding philosophy that drives development teams to frequently implement small changes and check-in code to version control repositories. Because most modern applications require developing code on different platforms and tools, the team needs a mechanism to integrate and validate its changes.
Continuous Delivery picks up where continuous Integration left its work. It automates the delivery of applications to selected infrastructure environments. Most teams work with multiple environments other than the production, such as development and testing environments, and CD ensures an automated way to push code changes.
You can also check our in-depth blog on CI/CD for more information.
Q4. What does CAMS stand for in DevOps?
Culture
DevOps methodology aims to bring unity among different teams to work as a single entity to achieve a designated target for the organization. Since the teams are working together, it helps to create a positive attitude or culture among the teams, which improves the overall environment for the teams to work.
Automation
This is the most important factor of the DevOps culture. Automation aims to build a system that eliminates human errors and can fix errors and repeat the successful process without any intervention or delays. Automation dramatically improves the workflow and productivity of the organization.
Measurement
It is all about monitoring and tracking the progress of various activities involved in the DevOps environment. Like Automation, measurement is also essential. By measuring the different system metrics, users can know how the system works or what needs to be done to increase performance, productivity, etc., for the software development lifecycle.
Sharing
The critical success of DevOps in any organization is by sharing the tools, discoveries, and knowledge among different teams. It has many benefits inside and outside the organization, i.e. finding people who have similar requirements will create newer opportunities to collaborate. Also, Company can eliminate redundant works.
Q5. What are the different phases in DevOps?
- Plan: This is the fundamental stage in which, all the requirements of the project, like the time required for each stage, its cost, etc., are discussed. This helps everyone in the team to get a brief idea about the project.
- Code: The code is written in this stage according to the client’s project requirements. In this codes are written in the form of small segments of codes called units.
- Build: Building of the units is done in this step.
- Test: Testing is done in this stage, and if there are mistakes found, it is returned for re-build.
- Integrate: All the units of the codes are integrated into this step.
- Deploy: codeDevOpsNow is deployed in this step on the client’s environment.
- Operate: Operations are performed on the code if required by the client.
- Monitor: Monitoring of the application is done over here in the client’s environment.
Q6. Give a use case where DevOps can be used in real-life.
Network cycling: Due to DevOps Deployment, Testing and rapid designing became many times faster. Nowadays it became effortless for the telco service provider to add security patches every day, which before used to be done only every three months. Through deployment and design, the new version of network cycling was being rolled out.
Etsy is a peer-to-peer e-commerce website that mainly focused on handmade or vintage items and supplies, as well as unique factory-manufactured items across all over the world. Etsy before struggled with slow, painful and complex site updates that caused the site to go down and it is directly affecting sales for millions of Etsy’s authorised users who sold their products through an online marketplace and risked driving them to the competitor.
DevOps helped with a new technical management team, Etsy transitioned from its waterfall model, which produced four-hour full-site deployments twice weekly, to a more agile and appropriate approach. Today, it has a fully automated deployment pipeline, and its continuous delivery practices have reportedly resulted in more than 50 deployments a day with fewer disruptions.
Q7. Where to use SSH?
Let’s first understand what is SSH it stands for Secure Shell and is an administrative protocol that lets users have access and control the remote servers over the Internet using the command-line interface.
SSH is a secured encrypted version of the previously known Telnet, which was unencrypted and not secure compared to SSH. This ensured that the communication with the remote server occur securely in an encrypted form.
It also has a mechanism for remote user authentication, input communication between the client and the host, and sending the output back to the client.
Q8. Explain Continuous Testing.
Continuous Testing is the technique of running automated tests as part of the delivery pipeline to quickly get feedback on the business risks associated with a software release candidate. It improves and expands test automation to keep up with the increasing complexity and speed of modern application development and delivery.
Q9. Difference between Ansible, Chef and Puppet?
Q10. What are the three crucial DevOps key performance indicators [KPIs]?
The following are some DevOps KPIs:
- Reduce the time it takes to recover from a failure on average.
- Increase the frequency with which deployments take place.
- The percentage of deployments that fail has decreased.
Intermediate Level
DevOps Interview Questions
The major difference between Continuous Deployment and Continuous Delivery are given below:
Q12. Can you tell me about Memcached?
In the following scenarios, Memcached can be used:
- In social networking domains such as Facebook, profile caching is used.
- Caching of web pages in the content aggregation domain.
- In the sphere of ad targeting, profile tracking is used.
- In the e-commerce, gaming, and entertainment domains, session caching is used.
- In the sphere of location-based services, database query optimization and scaling are important.
Memcached’s Advantages:
- The use of Memcached speeds up application processes by decreasing database hits and reducing I/O access.
- It aids in recognising which actions are more frequently taken and deciding what to cache.
You can use version control to:
- Revert files to a previous state.
- Reset the project to its original state.
- Changes over time can be compared.
- Check to see who made the most recent changes to something that might be causing an issue.
- Who was the first to bring up a problem, and when did they do so?
Q14. What are the benefits of using version control?
- With Version Control System (VCS), At any time, any team member can work on any file without restriction. Later, you’ll be able to merge all of the modifications into a standard version using VCS.
- Inside the VCS, all previous versions and variants are properly stored. You can request any version at any moment, and you’ll have a snapshot of the entire project at your fingertips.
- Your VCS needs you to indicate what was changed each time you save a new version of your project. You may also examine exactly what was modified in the file’s content. You’ll be able to see who made what changes to the project as a result of this.
- When using a distributed VCS like Git, all team members have access to the project’s whole history, so if the central server goes down, you may use any of your teammate’s local Git repositories.
Q15. Define the various branching strategies used in the version control system?
In version control systems like git, branching is a basic idea that supports team communication. The following are some of the most regularly utilised branching types:
Branched features
- This branching type assures that a project’s specific feature is preserved in a branch.
- The branch is then merged into the main branch once the feature has been completely confirmed.
Branched tasks
- Each task is kept in its own branch, with the branch name as the task key.
- By naming the branch after a task, it’s simple to figure out which task is covered by which branch.
Release branching
- This branching is used when a set of features for a release has been finalised and may be cloned into the release branch. This branch will not receive any more features.
- In a release branch, only bug fixes, documentation, and release-related activities are performed.
- When everything is finished, the releases are merged into the main branch and given a version number.
- These modifications must also be put into the development branch in order to continue working on new features
Q16. Can you list down specific KPIs which are used for gauging the success of DevOps?
- Application utilisation, performance, and traffic are some of the prominent KPIs used to measure DevOps success.
- Test Case that is Automated Percentage of students who pass.
- Availability of the Application
- Requests for volume changes
- The frequency and duration of successful deployments
- Rates of error/failure
- Deployment failures
- Mean time to detection (MTTD)
- Mean time to recovery (MTTR)
Q17. What is CBD in DevOps?
CBD stands for Component-Based Development. It is a unique way of approaching product development. Here, developers keep looking for existing well-defined, tested, and verified code components and relieve developers of developing from scratch.
Q18. Explain some basic Git commands?
Below are some basic Git commands:
Q19. What is Resilience Testing?
Resilience Testing is a software process that tests the application for its behaviour under uncontrolled and chaotic scenarios. It also ensures that the data and functionality are not lost after encountering a failure.
Q20. Can you differentiate between continuous Testing and automation testing?
The difference between continuous Testing and automation testing is given below:
| Continuous Testing | Automation Testing |
|---|---|
| This is executing all the automated test cases and is done as part of the delivery process. | This process replaces manual Testing by helping the developers create test cases that can be run multiple times without manual intervention. |
| This process focuses on the business risks associated with releasing software as early as possible. | This process helps the developer to know whether the features they have developed are bug-free or not by having a set of pass/fail points as a reference. |
Advance Level
DevOps Interview Questions
Q21. How does Ansible work?
There are two types of servers in Ansible:
- Controlling machines
- Nodes
For this to function, Ansible must be installed on the controlling system, and the nodes must be handled through SSH. The node’s location would be set and configured in the controlling machine’s inventory.
Due to its agentless design, Ansible does not require any installations on remote node servers. As a result, no background processes are required for handling remote nodes.
Using Ansible Playbooks and an SSH connection, Ansible can manage a large number of nodes from a single controlling system. Playbooks are written in the YAML language and can handle a variety of activities.
Q22. Please explain the “Shift left to reduce failure” concept in DevOps?
- The left side of the cycle consists of the planning, design, and development phase.
- The right side of the cycle includes stress testing, production staging, and user acceptance.
Shifting left in DevOps simply refers to moving as many jobs that typically occur at the end of the application development lifecycle as possible into the earlier phases. We can see from the graph below that if the left shift operations are followed, the odds of errors occurring later in the application development process are greatly reduced because they would have been discovered and solved sooner.
Q23. What do you know about post mortem meetings?
Q24. Explain how you can move or copy Jenkins from one server to another?
There are several options for doing so, which I’ve listed below:
You can do the following:
- Copy the relevant job directory from one Jenkins installation to another to move a job.
- Make a clone of a job directory with a different name to copy an existing job.
- Rename a directory to rename an existing job.
If you rename a job, any other job that attempts to call the renamed job will need to be renamed as well.
Q25. How will you secure Jenkins?There are multiple ways too, so I have mentioned the may in which I will do it, but If you have any other way of doing it, you can mention it in the comments section below:
- Ensure global security is on.
- Ensure that Jenkins is integrated with my Company’s user directory with the appropriate plugin.
- Ensure that matrix/Project matrix is enabled to fine-tune access.
- Automate the process of setting rights/privileges in Jenkins with a custom version controlled script.
- Limit physical access to Jenkins data/folders.
- Periodically run security audits on same.
Q26. How exactly are containers different from hypervisor virtualization?
Given below are some differences. Make sure you include these differences in your answer:
You can also check our blog for more information about Container (Docker) vs Virtual Machines
Q27: What is Pair Programming?
Pair programming is an engineering practice where two programmers work on the same system, same design, and duplicate code. They follow the rules of “Extreme Programming”. Here, one programmer is termed “driver” while the other acts as “observer”, which continuously monitors the project progress to identify any further problems.
Q28: Explain the Dogpile effect? How can it be prevented?
It is referred to as that event that occurs when the cache expires (or is invalidated), and multiple requests are hit to the website at the same time. It is also referred to as cache stampede, which can occur when massive parallel computing systems employing caching strategies are subjected to a very high load. The most common way of preventing dogpiling is by implementing semaphore locks in the cache. When the cache expires in this system, the first process to acquire the lock will generate the new value to the cache.
Q29. Explain the different Selenium components?
Selenium has the following components:
Selenium Integrated Development Environment (IDE)
- It has a simple framework and should be used for prototyping.
- It has an easy-to-install Firefox plugin.
Selenium Remote Control (RC)
Testing framework for a developer to write code in any programming language (Java, PHP, Perl, C#, etc.).
Selenium WebDriver
- Applies a better approach to automate browser activities.
- It does not rely on JavaScript.
Selenium Grid
Works with Selenium RC and runs tests on different nodes using browsers.
Q30. What are the tests that Selenium supports?
- Functional testing – This is a sort of black-box testing in which the test cases are built around the software specification.
- Regression Testing – This type of testing aids in the detection of new errors, regressions, and other issues in various functional and non-functional sections of code following a change.
- Load Testing – This type of testing examines a device’s response after it has been subjected to a load. It is conducted out to investigate the system’s behaviour under specific conditions.
Download the Complete DevOps Sample Interview Questions
When you have tested your knowledge by answering these DevOps sample interview questions, I hope you have a clear stand in terms of your DevOps interview preparation.
Note: K21Academy also offers a complete DevOps Interview Preparation Questions Prep Guide where learners get to practise questions to test their DevOps before the actual interview.
To download the complete DevOps Sample Interview Questions guide click here.
If you feel you are lagging somewhere and you need to buckle up your preparation process, then you can enrol for the K21Academy [DOFD] DevOps Foundation certification training course to clear the final exam successfully.
Related/References
- [DOFD] DevOps Foundation Certification Exam: Everything You Need To Know
- What Is DevOps | DevOps Principles | Advantages Of DevOps | Why DevOps?
- Agile Methodology and DevOps | DevOps and Agile Relationship
- DevOps Best Practices
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