Top 20 DevOps Questions for Acing Interview

Are you a DevOps engineer or considering becoming one? If that’s the case, you’ve come to the right place. Our Experienced Interviewers listed dozens of possible questions that interviewers ask potential DevOps hires in my article DevOps Interview Questions.

So without wasting time, Any time Let’s get going. Here is a list of the most frequently asked 20 questions that will undoubtedly assist you in the interview.

1. What are the most popular DevOps tools? On what tools did you work?

 

The most widely used DevOps tools are listed below:

 

  • Git is a version control system.

  • Jenkins is a tool for continuous integration.

  • Selenium is a continuous testing framework.

  • Chef, Puppet Configuration Management and Deployment Tools with Ansible

  • Continuous Monitoring Tool Nagios

  • Containerization software Docker

 

 


2. How do all of these tools interact?

 

A generic logical flow is shown below, in which everything is automated for seamless delivery. However, depending on the requirements, this flow may differ from one organisation to the next.

 

  • Developers create the code, which is then managed by Version Control System tools such as Git.

  • The code is sent to the Git repository by the developers, and any changes made to the code are committed to this repository.

  • Jenkins uses the Git plugin to pull this code from the repository and builds it with Ant or Maven.

  • Puppet and other configuration management tools deploy and provision testing environments, and Jenkins then releases this code to the test environment, where it is tested with tools like Selenium.

  • Jenkins sends the code to the production server after it has been tested (even the production server is provisioned & maintained by tools like a puppet).

  • It is continuously monitored after deployment using tools like Nagios.

  • Docker containers provide a testing environment for building features to be tested.

 

 

 

 3. What is the most important goal that DevOps assists us with?

 

The most important thing DevOps helps us achieve, according to us, is getting changes into production as quickly as possible while minimising software quality assurance and compliance risks. DevOps’ main goal is to achieve this.

However, there are numerous other advantages to DevOps. Clearer communication and better working relationships between teams, for example, where the Ops and Dev teams collaborate to deliver high-quality software, resulting in higher customer satisfaction.





4 . Give an example of how DevOps can be used in industry or in real life.

 

There are many industries that use DevOps, so you can mention any of them, or you can look at the example below:

Etsy is a peer-to-peer e-commerce site that specialises in handmade and vintage items, as well as unique factory-made items. Etsy was plagued by slow, inconvenient site updates that frequently brought the site down. It had an impact on sales for millions of Etsy users who sold goods on the online marketplace, and it had the potential to drive them to a competitor.

Etsy changed its waterfall model, which produced four-hour full-site deployments twice weekly, to a more agile approach with the help of a new technical management team.

 

 



5. Explain your knowledge and expertise on both the software development and technical operations sides of a company you’ve previously worked with.

 

 Share your previous work experience and try to explain how flexible you were in that position. Consider the following example:

Almost all DevOps engineers work in a 24/7 business-critical online environment. I was adaptable to on-call responsibilities and ready to assume real-time, live-system responsibility. To support continuous software deployments, I successfully automated processes. I have experience with public/private clouds, Chef or Puppet tools, Python and PHP scripting and automation, and an Agile background.

 

 

 

 6. What are the phases of the DevOps methodology?

 

The following are the stages of the DevOps lifecycle:

 

  • Plan – During this stage, all of the project’s requirements are discussed, as well as everything related to the project, such as time for each stage, cost, and so on. This will give everyone on the team a quick overview of the project.

  •  code is written here according to the client’s specifications. Codes are written in the form of units, which are small codes.

  • This step involves the construction of the units.

  • Testing is carried out at this stage, and if any errors are discovered, the product is returned for re-construction.

  • Integrate – This step incorporates all of the code’s units.

  •  Deploy In this step, DevOpsNow is installed on the client’s system.

  • If necessary, operations are performed on the code.

  • The application is monitored here in the client’s environment.



 

7.  What are the key performance indicators (KPIs) used to measure the success of a DevOps team?

 

The meaning of KPI Key Performance Indicators is used to assess a DevOps team’s performance, identify errors, and correct them. This aids the DevOps team’s productivity, which has a direct impact on revenue.

 

  • Change Failure Rates: This is a metric for calculating the number of deployment failures.

  • The time it takes to recover from a failed deployment is known as the meantime to recovery (MTTR).

  • Lead time: This is used to determine how long it takes to deploy in a production environment.

  • The frequency with which a new feature is deployed is measured here.

  • Change volume is a metric for determining how much existing code has been modified.

  • Total application development time is measured by cycle time.

  • Customer Ticket: This allows us to track the number of errors that the end-user has identified.

  • Availability: This is used to calculate the application’s downtime.

  • The defect escape rate allows us to calculate the number of issues that must be identified as early as possible. 

  • Time of detection: This helps you understand whether your response time and application monitoring processes are functioning correctly.

 

 

 

8.  Explain how you used branching strategies.

 

This question is meant to test your branching experience, so tell them about how you used branching in your previous job and for what purpose. For more information, see the following:

Feature branching

A feature branch model keeps all changes for a specific feature contained within a branch. The branch is merged into the master once the feature has been fully tested and validated by automated tests.

 

Task branching

Each task is implemented on its own branch in this model, and the task key is included in the branch name. Simply look for the task key in the branch name to see which code implements which task.

This branch should be used.

 

Release branching

You can clone the develop branch to create a Release branch once it has enough features for a release. This branch kicks off the next release cycle, so no new features can be added after this point; only bug fixes, documentation generation, and other release-related tasks should be placed here. The release is merged into the master and given a version number once it is ready to ship. It should also be merged back into the development branch, which may have progressed since the initial release.



Finally, tell them that branching strategies differ from one organisation to the next and that I am familiar with basic branching operations such as delete, merge, and checking out a branch.

 

 

 

 9. What does version control entail?

 

This will most likely be the easiest question in the interview. My recommendation is to start by defining version control. It’s a system that keeps track of changes to a file or set of files over time so you can go back to previous versions. Version control systems have a central shared repository where collaborators can commit changes to a file or set of files. You can then discuss the benefits of version control.

 

You can use version control to:

 

  • Restore files to their previous state.

  • Revert the entire project to its original state.

  • Compare and contrast changes over time.

  • See who made the most recent changes to something that might be causing a problem.

  • When and who brought up a problem.






10. What is Git, and what does it mean?

 

We recommend that you start by explaining how git works. Please see the following explanation:

 

Git is a version control system that uses a distributed approach (DVCS). It can keep track of changes to a file and allow you to undo any of them.

 

Its distributed architecture offers a number of advantages over other Version Control Systems (VCS) such as SVN. For example, it does not rely on a central server to store all versions of a project’s files. Instead, each developer “clones” a copy of a repository, which I labelled “Local repository” in the diagram below, and keeps the project’s entire history on his hard drive. so that in the event of a server outage, all you need is one of your teammate’s local Git repositories to recover.

 

There is also a central cloud repository where developers can commit changes and share them with other teammates, and a “Remote repository,” where all collaborators are committing changes.

 

 

 

11. What does Git bisect mean? How can you use it to figure out where a (regression) bug came from?

 

I recommend that you start by giving a brief definition of Git bisect. Git bisect is used to use binary search to find the commit that introduced a bug. 

git bisect

Now that you’ve mentioned the command, explain what this command does. This command employs a binary search algorithm to determine which commit in your project’s history caused the bug. You use it by first telling it about a “bad” commit that contains the bug and a “good” commit that was made before the bug was introduced. Then Git bisect picks a commit between those two endpoints and asks you whether the selected commit is “good” or “bad”. It continues narrowing down the range until it finds the exact commit that introduced the change.

 

 


12. What is Git rebase and how can it be used to resolve feature branch conflicts before merging?

 

To begin, I recommend defining git rebase as a command that merges another branch into the branch where you’re currently working and moves all local commits ahead of the rebased branch to the top of the branch’s history.

If a feature branch was created from the master and the master branch has received new commits since then, Git rebases can be used to move the feature branch to the tip of the master.

The command effectively replays the changes made in the feature branch at the master’s tip, allowing conflicts to be resolved along the way. When done correctly, this allows the feature branch to be quickly merged into the master.

 

 


13. How do you set up a Git repository so that code sanity checking tools are run right before commits, and that commits are prevented if the test fails?

 

We recommend that you start by giving a brief overview of sanity checking. Sanity or smoke test determines whether further testing is possible and reasonable.

Now, explain how you can accomplish this using a simple script linked to the repository’s pre-commit hook. The pre-commit hook is triggered just below:

 

fore a commit is made, even before a commit message is required. Other tools, such as linters, can be run in this script to perform sanity checks on the changes being committed to the repository.

Finally, give an example using the script 

 

				
					#!/bin/sh
files=$(git diff --cached --name-only --diff-filter=ACM | grep '.go$')
if [ -z files ]; then
exit 0
fi
unfmtd=$(gofmt -l $files)
if [ -z unfmtd ]; then
exit 0
fi
echo “Some .go files are not fmt’d”
exit 1</p>
<p style="text-align: justify;"><span>



				
			

 

 

This script checks to see if any .go file that is about to be committed needs to be passed through the standard Go source code formatting tool gofmt. By exiting with a non-zero status, the script effectively prevents the commit from being applied to the repository.

 

 

 

 

14.  How do you make a script that runs whenever a repository receives new commits via push?

 

There are three ways to set up a script to run every time a repository receives new commits via push: define a pre-receive, update, or post-receive hook, depending on when the script should be triggered.

 

When commits are pushed to the destination repository, the pre-receive hook is triggered. Before any references are updated, any script bound to this hook will be executed. This hook is useful for running scripts to enforce development policies.

 

The update hook is similar to the pre-receive hook in that it is triggered before any updates are made. The update hook, on the other hand, is called once for every commit that has been pushed to the destination repository.

 

Finally, after the updates have been accepted into the destination repository, the repository’s post-receive hook is called. This is a great place to set up simple deployment scripts, launch continuous integration systems, send repository maintainer notifications, and so on.

 

Hooks are not versioned and are unique to each Git repository. Scripts can be created in the hooks directory of the “.git” directory, or they can be placed within the directory.

 

 

 

 

 15. What are the distinctions between Git Merge and Git Rebase?

 

Both are merging mechanisms, but the difference between Git Merge and Git Rebase is that Git Merge logs will show the complete history of commits, whereas Git Rebase logs will not.

 

The logs, however, are rearranged when using Git Rebase. The logs have been rearranged to make them look more linear and understandable. This is also a disadvantage because other team members will be confused as to how the various commits were merged.

 

 

 

 16. Can you explain the DevOps concept of “shift left to reduce failure”?

 

Shift left is a DevOps concept for improving security, performance, and other factors. Let us take an example: if we look at all of the phases in DevOps, we can say that security is tested before the deployment step. We can include security in the development phase on the left by using the left shift method. [will be depicted in a diagram] We can integrate with all phases of development, including before development and during testing. This most likely raises the level of security by detecting errors at an early stage.

 

 

 

17.  Why do you need Continuous Development and Testing Integration?

 

You should concentrate on the importance of Continuous Integration in this response. We recommend that you include the following explanation in your response:

By replacing the traditional practice of testing after all development, Continuous Integration of Dev and Testing improves the quality of software and reduces the time it takes to deliver it. Because developers must integrate code into a shared repository several times per day, it allows the development team to easily detect and locate problems early (more frequently). Each check-in is then tested automatically.



 

 

18. What are the success factors for Continuous Integration?

 

Here you have to mention the requirements for Continuous Integration. You could include the following points in your answer:

  • Maintain a code repository

  • Automate the build

  • Make the build self-testing

  • Everyone commits to the baseline every day

  • Every commit (to baseline) should be built

  • Keep the build fast

  • Test in a clone of the production environment

  • Make it easy to get the latest deliverables

  • Everyone can see the results of the latest build

  • Automate deployment

 





19. What are the steps for moving or copying Jenkins from one server to another?

 

This task will be accomplished by copying the jobs directory from the old to the new server. There are several options for doing so, which I’ve listed below:

  • Copy the corresponding 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, you must also rename any other jobs that attempt to call the renamed job.

 

 

20. How would you set up a Jenkins job?


A pattern is a set of beliefs about how to solve a problem. Now, an anti-pattern can be defined as a method that may help us solve the problem in the short term but may harm our system in the long run [i.e., it demonstrates how not to approach a problem].
The following are some of the anti-patterns we see in DevOps:

 

  • DevOps is a method, not a mindset.

  • DevOps is synonymous with Agile.

  • A separate DevOps group should be formed.

  • DevOps solves all issues.

  • Developers running a production environment are referred to as DevOps.

  • Development-driven management is followed by DevOps.

  • DevOps isn’t particularly concerned with development.

  • We will not implement DevOps because we are a unique organisation that does not follow the crowd.

  • Since we lack the necessary personnel, we are unable to implement a DevOps culture.

 

 



This is the end of our topic. We hope we helped you in some way. The topics covered in this Core DevOps Interview Questions blog are among the most sought-after skillsets for a DevOps professional, according to recruiters. These DevOps  Interview Questions will undoubtedly assist you in acing your job interview.


Best wishes for your interview!


If you still have any queries, please let us know in the comment section.