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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 blindspots.
• 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.

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.

It is a DevOps open-source automation tool which helps in modernizing the development and deployment process of applications in faster manner. It has gained popularity due to simplicity in understanding, using, and adopting it which largely helped people across the globe to work in a collaborative manner.

A pipeline, in GENERAL, is a SET of automated tasks/processes defined and followed by the software engineering team. DevOps pipeline is a pipeline which allows the DevOps engineers and the software developers to efficiently and RELIABLY compile, build and deploy the software code to the production environments in a hassle free manner.

Following image shows an EXAMPLE of an effective DevOps pipeline for deployment.

The flow is as follows:

• Developer works on completing a functionality.
• Developer deploys his code to the test environment.
• Testers work on validating the feature. Business team can intervene and provide feedback too.
• Developers work on the test and business feedback in continuous collaboration manner.
• The code is then RELEASED to the production and validated again.

The difference between CONTINUOUS testing and automation testing is given below:

Resilience Testing is a software process that tests the application for its behavior under UNCONTROLLED and CHAOTIC scenarios. It also ensures that the data and FUNCTIONALITY are not lost after encountering a FAILURE.

CBD stands for Component-Based Development. It is a UNIQUE way for approaching product development. Here, DEVELOPERS keep looking for existing well-defined, TESTED, and VERIFIED components of code and relieve the developer of developing from SCRATCH.

KPIs stands for KEY PERFORMANCE INDICATORS. Some of the POPULAR KPIs used for gauging the SUCCESS of DevOps are:

• Application usage, performance, and traffic
• Automated Test Case Pass Percentage.
• Application Availability
• Change volume requests
• Customer tickets
• Successful deployment frequency and time
• Error/Failure rates
• Failed deployments
• Meantime to detection (MTTD)
• Meantime to recovery (MTTR)

Branching is a very important concept in version control SYSTEMS like git which facilitates team collaboration. Some of the most commonly used branching types are:

Feature branching

• This branching type ensures that a particular feature of a project is maintained in a branch.
• Once the feature is fully validated, the branch is then merged into the main branch.

Task branching

• Here, each task is maintained in its own branch with the task key being the branch name.
• Naming the branch name as a task name makes it EASY to identify what task is getting covered in what branch.

Release branching

• This type of branching is done once a set of FEATURES meant for a release are completed, they can be cloned into a branch called the release branch. Any further features will not be added to this branch.
• Only bug fixes, documentation, and release-related activities are done in a release branch.
• Once the things are ready, the RELEASES get merged into the main branch and are tagged with the release version number.
• These changes also need to be pushed into the develop branch which WOULD have progressed with new feature development.

The branching strategies followed would vary from company to company based on their requirements and strategies.

Memcached is an open-source and free in-memory object caching system that has high performance and is distributed and GENERIC in nature. It is mainly used for SPEEDING the dynamic web applications by reducing the database load.

Memcached can be used in the following cases:

• Profile caching in social networking domains like Facebook.
• Web page caching in the CONTENT aggregation domain.
• Profile tracking in Ad targeting domain.
• Session caching in e-commerce, gaming, and entertainment domain.
• Database query optimization and scaling in the Location-based services domain.

Benefits of Memcached:

• Using Memcached speeds up the APPLICATION processes by reducing the hits to a database and reducing the I/O access.
• It helps in determining what steps are more frequently FOLLOWED and helps in deciding what to cache.

Some of the drawbacks of using Memcached are:

• In case of failure, the data is lost as it is neither a persistent data store nor a database.
• It is not an application-specific cache.
• Large objects cannot be cached.

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 DevOps culture.

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

DevOps is a practice or a CULTURE that allows the collaboration of the development team and the operations team to come together for successful product development. This involves making use of practices like continuous development, integration, testing, deployment, and monitoring of the SDLC cycle.

DevOps tries to REDUCE the GAP between the developers and the operations team for the effective launch of the product.

Agile is nothing but a software development methodology that focuses on incremental, iterative, and rapid releases of software features by involving the customer by means of feedback. This methodology REMOVES the gap between the requirement UNDERSTANDING of the clients and the developers.

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 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 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.