DevOps Interview Questions
The DevOps is a combination of two words one is software Development, and second is Operations. It allows a single team to handle the entire application lifecycle, from development to testing, deployment, and operations. DevOps helps you to reduce the disconnection between software developers, quality assurance (QA) engineers, and system administrators.

Characteristics DevOps
Basic premise A collaboration of development and operations teams. It is more of a cultural shift.
Related to Agile methodology
Priorities Resource management, communication, and teamwork
Benefits Speed, functionality, stability, and innovation
A DevOps engineer is a person who works with both software developers and the IT staff to ensure smooth code releases. They are generally developers who develop an interest in the deployment and operations domain or the system admins who develop a passion for coding to move towards the development side.
In short, a DevOps engineer is someone who has an understanding of SDLC (Software Development Lifecycle) and of automation tools for developing CI/CD pipelines.
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 achieving 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.
The differences between the two are listed down in the table below.
Features DevOps Agile
Agility Agility in 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
The principles behind DevOps are :
* Continuous deployment
* Infrastructure as code
* Automation
* Monitoring
* Security
Here are some popular tools of DevOps, such as :
Jenkins : Jenkins is a DevOps tool for monitoring the execution of repeated tasks. Jenkins is a software that allows continuous integration. And it will be installed on a server where the central build will take place.

Ansible : Ansible is a leading DevOps tool. Ansible is an open-source IT engine that automates application deployment, cloud provisioning, intra service orchestration, and other IT tools.

Nagios : Nagios is one of the more useful tools for DevOps. It can determine the errors and rectify them with the help of network, infrastructure, server, and log monitoring systems.

Docker : Docker is a high-end DevOps tool that allows building, ship, and run distributed applications on multiple systems.

Git : Git is an open-source distributed version control system that is freely available for everyone. It is designed to handle minor to major projects with speed and efficiency.
Following are some useful prerequisites for DevOps implementation :
* Proper communication between the team members.
* At least one version control software.
* Automated testing.
* Automated deployment.
The core operation of DevOps with application development and infrastructure are :
Application development :
* Code building
* Code coverage
* Unit testing
* Packaging
* Deployment

Infrastructure :
* Provisioning
* Configuration
* Orchestration
* Deployment
HTTP or Hypertext Transfer Protocol works in a client–server model like the most other protocols. HTTP provides a way to interact with web resources by transmitting hypertext messages between clients and servers.
Technical benefits :
* Continuous software delivery
* Less complex problems to fix
* Faster bug resolution

Business benefits:
* Faster delivery of features for customer satisfaction
* More stable operating environments
* More time available to add product value