Interview’s Questions

this category contains the most asked questions in DevOps interviews

interview's questions and answers

HR Interview Questions and Answers: Part -1

vivek bangare

Vivek Bangare


HR Interview Questions and Answers: Part-1

Hello everyone, In this article, we will mostly talk about HR interview questions and answers. These are fresher as well as experienced ones. I am creating a series of HR questions and Answers in multiple parts. Let’s begin.

What is the reason for applying for this job?

I've been working for several years on gaining skills in your company(industry). I feel I have the knowledge, skills and qualifications you are looking for, along with a unique perspective coming from a different industry. 

Why are you applying for this job?

I noticed that the part of my previous positions I enjoyed the most were those that aligned with what's listed in your job description, like...(mentions some example related to your work experience).

While I am grateful for my time at my current company, I feel that it's time to move into a role more tailored to my talents where I can continue to grow.

Tell me what you know about the role.

From the job description, I understand that you are looking for a...(mentions a few examples of required skills).

Can you tell me more about why this position is open and what needs the team needs?

When can you start?

After getting an offer, I am able to start 60 days (mentions your notice period) later to provide time for my current role to be filled.

Describe who you are? or Tell me about your background.

Well, I am confident, hardworking and a very professional individual. I always carried out all the tasks assigned to me without hesitation.

I have also been a good mentor to my juniors and never hesitate to ask if something I don't know.

On the other hand, I am creative and love to test my boundaries.

Why did you leave your previous role?

I'm looking for better career prospects and opportunities for professional growth. It wasn't aligned with my longer-term career goals.

I'm looking for new challenges at work that align with my strength. I was no longer finding the work full-filling. My company was restructuring so it's an opportunity for change.


interview's questions and answers

Interview Questions and Answers in Linux: Part-3

vivek bangare

Vivek Bangare


Interview Questions and Answers in Linux: Part-3

Hello everyone, This is the third part of the interview questions and answers in Linux. Along with that will go through some examples also. I will create a series of questions and answers for beginners to advanced levels.

more vs less command

Both are used for viewing large files page-wise.

'less' is faster, it doesn't load the entire file at once, and allows navigations using up/down keys.

What does 'shred' do?

It is used to permanently delete data that you don't want to be recovered. 

Difference between find vs locate
  • works in real-time
  • searches all directories.
  • Examine each file one by one.
  • requires a lot of I/O calls, and takes longer to get results.
  • Works in offline mode.
  • Searches files in updated db.
  • Comparatively quicker but the results are not as fresh as 'find'. 
command to print only 60 lines from file

pr -l 60 {file_name} [default 66]

How to collect reports or saved system information and log servers like CPU, memory disks, interrupts, network interfaces?
  • sar [commands]
  • logs are stored in /var/log/sadd file
How to verify memory status and cpu status as linux admin?

vmstat or free

Difference between cron and anacron
  • Granularity is in minutes.
  • Normal users can schedule.
  • Expects the system up and running.
  • Granularity is in days.
  • Only superusers can schedule.
  • Doesn't expect to execute as soon as the system is up and running. 
Shadow password file

A shadow password system file is known as /etc/shadow. It stores encrypted user passwords and it can only access by a root user.

Earlier Linux file system stores in /etc/passwd but it is vulnerable, to avoid this vulnerability newer version of Linux stores password in /etc/shadow (it's in hashed)

interview's questions and answers

Interview Questions and Answers in Linux: Part-2

vivek bangare

Vivek Bangare


Interview Questions and Answers in Linux: Part-2

Hello everyone, This is the second part of the interview questions and answers in Linux. Along with that will go through some examples also. I will create a series of questions and answers for beginners to advanced levels.

Difference between Linux and Unix
  • It's an open source.
  • Free downloads and distribution/cheaper options.
  • Lightweight with no need for high-end hardware.
  • Users: Home users, developers etc.
  • Ubuntu, Debian, Red-Hat, Solaris.
  • installed on mobile phones, desktops, tablets video games consoles etc.
  • No source code for the general public.
  • Not free, different prices for different variants.
  • Need specific hardware, is comparatively costly.
  • Mainly developed for mainframe servers and workstations except for OsX.
  • AIX, HP-UX, BSD, Iris.
  • Used internet servers, mainframes and high-end computers.
Components of linux

Kernel - Core part

System Library - Special functions using which application programs access Kernel features.

System Utility - Responsible for performing individuals and specialized functions.

Why Linux is more secured than other OS?
  • Users don't have root access.
  • The virus can attack local files and folders only.
  • All Linux accesses are recorded in log files.
  • iptables to manage incoming and outgoing traffic.
grep command
  • grep (Global Regular Expression Print)
  • it is a search command; that uses pattern-based searches.
  • Uses options and parameters specified along with the command line.

Ex: cat /etc/users/user.txt | grep -i 'basictechno'

the above command will print a line which contains only 'basictechno' as a string.

root account (default account)

It's a live system admin's account.

Allows you to create and maintain user accounts and assign permissions.

root directory

The parent directory is represented by "/".

Contains all other directories and files.

Why should you avoid Telnet to administrator a system remotely?

The method of communication is insecure and The data is sent across the network without encryptions, in plain text format.

Types of files ownerships and changing them.

User - Owner/Creator of the file.

Group - All users in the group have the same permission.

Other - user with access to the file but not a part of that group.

Command: "chown"

Syntax: chown <newowner> <filename>

types of permissions for a file

  • Read (r) - open and read
  • Write (w) - modified content, renaming
  • Execute (x) - executing file
swap space and its advantage

Memory space comes into play when RAM doesn't have adequate memory to hold all executing programs.

Inactive memory pages are moved to swap space.

Soft and Hard mounting points.

Soft mount case - if the NFS client fails to receive a response from NFS servers, it reports an error without waiting.

Hard mount case - NFS client repeatedly tries to contact the server until a response is received.

interview's questions and answers

Interview Questions and Answers in Linux: Part-1

vivek bangare

Vivek Bangare


Top Interview Questions and Answers in Linux: Part-1

Hello everyone, In this article, we will mostly talk about top interview questions and answers in Linux. Along with that will go through some examples also. I will create a series of questions and answers for beginners to advanced levels.

Check Linux Kernal Version
  • uname -a
  • uname -v
  • uname -r
Verify current IP address in linux
  • ifconfig
  • ip addr show eth0
Free disk space

df -ah (h is used for human readable format)

How to verify manage services in linux?

Verifying service status:

  • service {service_name} status
  • systemctl status {service_name} // new one

for ex: systemctl status nginx

Start a specific service:

  • service {service_name} start
  • systemctl start {service_name}

for ex: systemctl start nginx

Stop a specific service:

  • service {service_name} stop
  • systemctl stop {service_name}

for ex: systemctl stop nginx

Restart a specific service:

  • service {service_name}restart
  • systemctl restart {service_name}

for ex: systemctl restart nginx

Size of directory

du -sh {directory_name}

How to open ports in linux?

netstat -tulpn

Verify CPU usage process

ps aux | grep {process_name}

for ex: ps aux | grep apache2


Deal with mount

ls /mnt

mount /dev/sda2 /mnt


Getting manual of any command

man {command}

Finding mount filesystem

findmnt /mnt

Unmount filesystem

sudo unmount /mnt

Manipulating data and generates reports
  • awk '{print}' {file_name}
  • awk '/manager/{print}' {file_name}
  • awk '{print} $1,$2' {file_name}
  • awk 'if($3=="B6") print $0;' {file_name}
  • awk 'BEGIN{for(i=1;i<=6;i++) print "squareof"', i; "is", i*i;}'
Stream editor
  • sed 's/unix/linux/' {file_name}
  • sed 's/unix/linux/2' {file_name}
  • sed 's/unix/linux/g' {file_name}
  • sed 's/unix/linux/3g' {file_name}
  • sed '3 s/unix/linux/' {file_name}
interview's questions and answers

Interview Questions and Answers in Docker : Part-1

vivek bangare

Vivek Bangare


Interview Questions and Answers in Docker : Part-1

Hello everyone, ‘Interview questions and answers in Docker‘, this article contains mostly asked interview questions and their answers. I am creating a series of questions and answers for beginners to advance.

Do you know why docker system prune is used? What does it do?

'docker system prune' is mostly used to remove all unused images, containers, and networks. Volumes are not pruned by default.

Will you lose your data, when a docker container exists?

Docker containers are designed to be stateless by default, meaning that data stored within the container itself is not persistent. However you can configure Docker to use  volumes or bind mounts to persist data outside the container

What is Docker? Docker lifecycle and Docker container state

Docker is an open-source platform that allows you to automate the deployment, scaling, and management of applications using containerization.

Docker lifecycle to the various stages  as follows:

  • Image Creation
  • Container Creation
  • Running state
  • Stopped state
  • Paused state
  • Deletion

Overall, Docker provides a flexible and efficient way to manage and deploy applications, allowing for easy container creation, starting, stopping, and deletion while maintaining the state of containers as needed.


Use of the docker save and docker load commands?

The docker save and docker load commands are used to save Docker images to a file and load them back into Docker, respectively. These commands are particularly useful when you need to transfer Docker images between different environments or when you want to back up your images for future use.

Default docker network driver, and how can you change it when running a Docker image?

The default network driver in Docker is the bridge network driver. When you run a Docker container without specifying a network driver, it automatically uses the bridge network.

To change the network driver when running a Docker image, you can specify the desired driver using the --network flag followed by the driver name. Here's an example:

docker run --network=<network-driver> <image>


Replace <network-driver> with the name of the desired network driver and <image> with the name of the Docker image you want to run.

Is there any problem with just using the latest tag in a container orchestration environment? What is considered best practice for image tagging?

Using the latest tag for Docker images in a container orchestration environment can introduce potential problems and is generally not considered a best practice. Here's why:

  • Lack of version control
  • Non-deterministic behavior
  • Inconsistent environments
What is Docker Swarm and which network driver should be used with it?

Docker Swarm is a native clustering and orchestration solution provided by Docker.

The recommended network driver is the overlay network driver. 

Docker Compose? What can it be used for?

Docker Compose is a tool provided by Docker that allows you to define and manage multi-container Docker applications.

Some key use cases and benefits of using Docker Compose:

  • Define and orchestrate multi-container applications
  • Easy setup and reproducibility
  • Simplified local development
  • Service scaling and load balancing
  • Service dependencies and ordering
  • Integration with Docker Swarm
Diffrence between entrypoint and cmd?


  • ENTRYPOINT specifies the command that is always executed when the container starts.
  • It provides the primary command or executable for the container.
  • If ENTRYPOINT is used in the Dockerfile, it will override any command specified with CMD at runtime.
  • ENTRYPOINT is typically used for defining the main application or process that runs inside the container.


  • CMD specifies the default arguments for the command defined in ENTRYPOINT, or it can be used to define the command itself if ENTRYPOINT is not specified.
  • CMD is optional and can be overridden when running the container by providing a command or arguments as parameters.
  • If both CMD and ENTRYPOINT are specified in the Dockerfile, the CMD values will be passed as arguments to the ENTRYPOINT command when the container starts.
  • CMD is typically used to provide default settings or arguments for the main command specified in ENTRYPOINT, but it can also be used to define a standalone command if ENTRYPOINT is not used.