What are the most widely used DevOps tools?
The most popular DevOps tools include:
- Selenium
- Puppet
- Chef
- Git
- Jenkins
- Ansible
- Docker
Which phases of DevOps are there?
The following are the stages of the DevOps lifecycle:
- Plan – A plan for the type of application that needs to be developed should be created first. It’s always a good idea to get a broad understanding of the development process.
- Code – The application is coded to meet the needs of the end-user.
- Build – Assemble the app by combining the numerous codes created in the previous steps.
- Test – The most important step in the application development process is testing. If required, test the application and rebuild it.
- Integrate – Several separate programmers’ codes are combined into one.
- Deploy – The code is placed in a cloud environment to be used later. Any new adjustments are verified not to disrupt the operation of a high-traffic website.
- Operate – If necessary, operations are done on the code.
- Monitor – The performance of the application is monitored. Changes are made to fit the needs of the end-user.
Mention a few of DevOps’ most important advantages
The following are the main advantages of DevOps:
- Advantages in terms of technology
- Software supply on a continuous basis
- Problems that are less difficult to solve
- Defects are detected earlier and corrected more quickly.
Benefits to the company
- Features are delivered more quickly.
- Operating settings that are stable
- Collaboration and communication between teams have improved.
How will you handle a project requiring DevOps implementation?
Standard ways for implementing DevOps in a specific project include the following:
- The initial stage
A two- to three-week assessment of the present process and implementation to identify areas for improvement so that the team can develop a road map for implementation.
- Stage two
Construct a proof-of-concept (PoC). Once it has been reviewed and approved, the team can begin implementing and rolling out the project plan.
- Stage three
The project is now prepared to apply DevOps by following a step-by-step process that includes version control, integration, testing, deployment, delivery, and monitoring.
The project is now prepared for DevOps implementation by following the correct steps for version control, integration, testing, deployment, delivery, and monitoring.
What is the role of configuration management in DevOps?
- Allows for the management and modification of numerous systems.
- Standardizes resource settings, which in turn simplifies the management of information technology infrastructure.
- It aids in the administration and management of several servers and ensures the infrastructure’s integrity.
How can continuous monitoring assist you in maintaining the system’s complete architecture?
Continuous monitoring is a process in DevOps that involves detecting, recognizing, and reporting any errors or risks in the system’s complete infrastructure.
- Ascertains that all services, applications, and resources are operating properly on the servers.
- Monitors the status of servers and evaluates whether or not apps are functioning properly.
- Allows for continuous auditing, transaction inspection, and monitored surveillance.
What is AWS’s role in DevOps?
In DevOps, AWS plays the following roles:
- Flexible services – Provides ready-to-use, flexible services that do not require the installation or configuration of software.
- Built for scalability – Using AWS services, you can manage a single instance or scale to thousands.
- Automation – AWS allows you to automate operations and processes, freeing up time to innovate.
- Secure – You can configure user rights and policies using AWS Identity and Access Management (IAM).
- AWS has a vast ecosystem of partners who integrate with and extend AWS services.
Name three key DevOps metrics
The following are the three most important KPIs:
- Meantime – The average time it takes to recover from a failure is called the meantime to failure recovery.
- Deployment frequency – The number of times a deployment takes place.
- Percentage of failed deployments – The number of times a deployment fails is expressed as a percentage.
Why has DevOps become so popular in recent years?
Before we go into the growing popularity of DevOps, let’s take a look at the sector’s current state. Begin by describing how major companies like Netflix and Facebook are using DevOps to automate and accelerate application deployment, and how this has helped them grow their businesses.
Using Facebook as an example, you may discuss how the company’s continuous deployment and code ownership models have helped it scale while maintaining a high quality of experience. Hundreds of lines of code are added without compromising the quality, stability, or security of the system.
Netflix should be your next use case. Similar approaches are followed by this streaming and on-demand video firm, which uses completely automated procedures and systems. Mention the following two organizations’ user bases: Facebook has a user base of 2 billion people, whereas Netflix has a global user base of more than 100 million people.
These are excellent instances of how DevOps can assist firms in increasing release success rates, reduce bug fix lead times, streamlining and continuous delivery through automation, and lower total staffing costs.
What are the advantages of implementing version control?
The following are some of the advantages of using Version Control:
- With the Version Control System, any team member can work on any file at any time (VCS). VCS will later allow the team to merge all of the changes into a single version.
- Every time we save a new version of the project, the VCS requests a brief synopsis of what was modified. We also get to see exactly what was changed in the file’s content. We’ll be able to observe who made what changes to the project as a result.
- All prior variants and versions are appropriately stored within the VCS. At any time, we’ll be able to request any version, and we’ll have a snapshot of the entire project at our fingers.
- A distributed VCS, such as Git, allows all team members to access the project’s whole history. This allows developers and other stakeholders to access any of the colleagues’ local Git repositories even if the main server is unavailable.
What is the Blue/Green Deployment Pattern?
This is a common way of continuous deployment for reducing downtime. This is where data is sent from one instance to the next. We must replace the old code with a new code version in order to include a new version of the code.
The new version is set in a green setting, while the old one is blue. After making changes to the previous version, we’ll need to create a new instance from the old one in order to run the newer version.
What is Automation Testing?
The technique of automating a manual method in order to test an application or system is known as automation testing. Automation testing comprises the use of stand-alone testing technologies to create test scripts that can be run repeatedly without requiring human intervention.
What advantages does automation testing provide?
Several advantages of automation testing include the following:
- Contributes to cost and time savings.
- Unattended execution is simple to accomplish.
- Large test matrices can be tested easily.
- Execution in parallel is enabled.
- Reduced human-caused errors, resulting in increased accuracy.
- Repeated execution of test tasks is supported.
What is the significance of continuous testing in DevOps?
Continuous Testing allows you to test any changes to the code right away. This eliminates problems like quality issues and releases delays that might arise when big-bang testing is postponed until the end of the cycle. Continuous Testing provides for higher-quality and more frequent releases in this way.
What are the most essential features of Continuous Testing tools?
- Test optimization – Ensures that tests produce trustworthy findings and information that may be used. Aspects include Test Data Management, Test Optimization Management, and Test Maintenance.
- Advanced Analysis – It uses automation in areas like scope assessment/prioritization, changes effect analysis, and static code analysis to prevent problems from developing in the first place and to achieve more within each cycle.
- Policy analysis – Ensures that all processes are followed. Test optimization ensures that tests produce trustworthy findings and information that may be used. Aspects include Test Data Management, Test Optimization Management, and Test Maintenance.
- Risk Assessment – Test coverage optimization, technical debt, risk mitigation responsibilities, and quality evaluation are all addressed to ensure the build is ready for the next stage.
- Service Virtualization – Assures the availability of real-world testing scenarios. Service visualization gives you access to a virtual depiction of the testing phases you’ll require, ensuring their availability and cutting down on the time it takes to set up the test environment.
- Requirements Traceability – Ensures no need for rework and those valid criteria are met. An object assessment is used to determine which conditions require extra validation, are in jeopardy, are performing as intended, are following the evolving business needs of the firm, and all regulatory standards are met.
How do you use Git to push a file from your computer to the GitHub repository?
To begin, link your local repository to your remote repository as follows:
git remote add origin [copied web address]
// Ex: git remote add origin https://github.com/computeman/test.git
Second, upload your file to a remote repository as follows:
git push origin master
Which of the following CLI commands can be used to rename files?
- git rm
- git mv
- git rm -r
- None of the above
The correct answer is git mv.
What is the procedure for reversing a public commit that has already been pushed?
You can revert a commit in one of two ways:
In a new commit, remove or fix the problematic file and submit it to the remote repository. Then, using the following command, commit it to the remote repository:
git commit –m "commit message"
Make a new commit that undoes all of the modifications done in the previous one. Use this command to get started:
git revert <commit id>
Example: git revert 96pe073kl
What is Git stash?
A developer working on one branch wants to transition to another to work on something different, but they don’t want to submit modifications to your incomplete work. Git stash is the solution to this problem. Git stash puts your updated tracked files on a stack of unfinished modifications that you can reapply whenever you want.
Explain the branching principle in Git
Let’s say you’re working on an app and you’d like to add a new feature to it. You can make a new branch and work on the new functionality there.
- You always work on the master branch by default.
- The circles on the branch represent the branch’s various commits.
- You can merge it with the main branch once you’ve finished all of the changes.
What is the purpose of using SSL certificates in Chef?
- SSL certificates are used to verify that each node has access to the correct data between the Chef server and the client.
- Every node has a pair of private and public keys. The Chef server stores the public key.
- When an SSL certificate is given to the server, it contains the node’s private key.
- The server compares this to the public key in order to identify the node and grant it access to the necessary data.
How to stop or disable the ‘httpd’ service when the system boots?
# systemctl disable httpd.service
# system disable httpd.service
# system disable httpd
# systemctl disable httpd.service
The correct answer is:
# systemctl disable httpd.service
What distinguishes chef-apply from chef-client?
chef-apply is a client-side application.
On the client system, chef-apply executes the recipe that was specified in the command.
$ chef-apply recipe_name.rb
chef-client is also run on the client system.
All the cookbooks in your server’s run list are applied to the client system when using chef-client.
$ knife chef-client
What are the resources in Puppet?
- Any configuration management tool’s basic units are called resources.
- These are a node’s characteristics, such as its software packages or services.
- In a catalog, a resource declaration outlines the action that will be performed on or with the resource.
- When the catalog is executed, it restores the desired state to the node.
What is an Ansible role?
Ansible roles are self-contained groups of tasks, variables, files, and templates that are embedded within a playbook.
Describe Docker’s architecture
- Docker is built on a client-server model.
- Docker Client is a command-running service. The REST API is used to translate the command, which is then submitted to the Docker Daemon (server).
- The Docker Daemon takes the request and communicates with the operating system in order to create Docker images and start Docker containers.
- A Docker image is a set of instructions that may be used to build containers.
- A Docker container is a single executable package that contains a program and all of its dependencies.
- Docker registry is a service that allows users to store and share Docker images.
What is the purpose of a Dockerfile?
- When using the build command to create Docker images, a Dockerfile is utilized.
- Any user can run the code to construct Docker containers using a Docker image.
- A Docker image is created and then uploaded to a Docker registry.
- Users can acquire the Docker image and build new containers whenever they wish from the Docker registry.
What is the procedure for creating a Docker container?
A user can either create their own Docker image or get one from Docker Hub (such as MySQL).
Docker now builds a new MySQL container using the existing Docker image. On top of the image layer, the container layer of the read-write filesystem is also generated.
- To make a Docker container, use the following command:
docker run -t –i MySQL
- To see a list of currently running containers, use the following command:
docker ps
What distinguishes a registry from a repository?
A Docker registry is a server-side open-source service that hosts and distributes Docker images whereas the repository is a collection of multiple Docker image versions.