Top 5 CI/CD Interview Q&A | DevOps FAQ |#devopsinterviewquestions | #jenkins |#devops #kubernetes

Summary

In this informative video, the host delves into the top 5 most common CI/CD interview questions and their answers. The discussion covers explaining a current CI/CD setup, handling secrets, deployment strategies including blue-green and canary deployments, and strategies for rollback in case of faults. Additionally, the video touches on Jenkins setup, backup, and scaling, providing insights into the most popular CI tool. The host invites viewers to share other relevant CI/CD interview questions in the comments.

Takeaways

• 🔧 The top 5 most common interview questions about CI/CD are discussed, focusing on setup, tools, and strategies.
• 🛠️ Explaining a current CI/CD setup involves detailing the tools used, such as GitHub and Jenkins, and the stages of the pipeline including build, test, and deployment.
• 🔑 Handling secrets in CI/CD pipelines is crucial and can be managed using platform-specific features or tools like HashiCorp Vault.
• 🚀 Deployment strategies such as Blue-Green and Canary are important for minimizing downtime and risks associated with new releases.
• 🔄 Blue-Green deployment allows for quick rollbacks by shifting traffic between two versions of an application, ensuring reliability.
• 🦀 Canary deployment gradually routes traffic to a new version of an application, allowing for monitoring and adjustments before full deployment.
• ❌ Strategies for dealing with faulty deployments include rollback pipelines and the use of Blue-Green deployment for easy traffic redirection.
• 📈 Jenkins is highlighted as a popular CI tool, with a focus on its setup, backup, and scaling capabilities.
• 🚀 Auto-scaling of Jenkins on cloud platforms like AWS can be managed using EC2 instances and predictive scaling for efficient resource use.
• 🔒 The importance of securing CI/CD pipelines with proper secret management is emphasized, as secrets are integral to modern applications.
• 🔄 The script calls for community engagement by inviting viewers to share additional CI/CD interview questions in the comments section.

Q & A

What are the top 5 most common CI/CD interview questions?

The top 5 CI/CD interview questions include: 1) Explain your current CI/CD setup. 2) How do you handle secrets in your CI/CD pipeline? 3) What is your deployment strategy? 4) How do you handle rollbacks if the deployed application is faulty? 5) How do you set up backup and scaling for Jenkins?

What does CI/CD stand for and why is it important in software development?

CI/CD stands for Continuous Integration and Continuous Delivery. It is important in software development as it allows for the automation of building, testing, and deployment processes, enabling teams to deliver code changes more frequently and reliably.

What are some common tools used in CI/CD setups?

Common tools used in CI/CD setups include GitHub for version control, Jenkins for continuous integration, and various cloud services or tools like AWS Systems Manager, Azure Vault, or HashiCorp Vault for managing secrets.

Can you describe the process of a Jenkins CI pipeline with multiple stages?

A Jenkins CI pipeline typically includes multiple stages such as build, where static code analysis and unit testing are performed; test, where further testing like smoke or functional testing is conducted; and deploy, where artifacts are built and deployed to the target environment like a Kubernetes cluster or application servers.

How do you secure secrets in a CI/CD pipeline when using GitHub Actions?

When using GitHub Actions, secrets can be secured by using the built-in secrets feature, which allows you to store and use encrypted secrets within your workflow.

What is Blue-Green deployment and how does it work?

Blue-Green deployment is a strategy where two identical environments (Blue and Green) are maintained. One environment is active while the other is idle. When a new version is ready, it is deployed to the idle environment. If the new version is stable, the load balancer is switched to direct traffic to the new environment, allowing for easy rollback if needed.

What is Canary deployment and how does it differ from Blue-Green deployment?

Canary deployment involves gradually shifting traffic from the old version of an application to a new version by slowly increasing the percentage of traffic directed to the new version. This differs from Blue-Green deployment, which switches traffic all at once after a new version has been fully deployed to the idle environment.

How can you handle a faulty deployment in a CI/CD pipeline?

Handling a faulty deployment can involve using a rollback pipeline or strategy, such as quickly switching traffic back to a previous stable version using Blue-Green deployment, or using load balancers to reroute traffic away from the faulty version.

What are some considerations for Jenkins backup and scaling?

Considerations for Jenkins backup and scaling include regularly backing up the .jenkins folder, using auto-scaling groups in cloud environments to handle variable build loads, and employing predictive scaling to anticipate traffic and adjust resources accordingly.

Why is Jenkins a popular choice for CI/CD tools according to the video?

Jenkins is a popular choice for CI/CD tools because it was chosen by 90% of the respondents in a poll conducted by the video creator on their YouTube channel, indicating its widespread use and preference in the industry.

How can you install Jenkins and what is the importance of understanding its installation process?

Jenkins can be installed using a simple curl command or through Docker. Understanding its installation process is important because it ensures that you can set up a Jenkins environment quickly and efficiently, which is crucial for establishing a CI/CD pipeline.

Outlines

00:00

🔧 Top 5 CI/CD Interview Questions and Answers

The script discusses the top 5 CI/CD interview questions, starting with explaining one's current CI/CD setup. It emphasizes the importance of detailing the tools and processes involved, such as using GitHub with Jenkins for CI, setting up webhooks, and describing the various stages of a Jenkins pipeline including build, test, and deployment stages. It also touches on the handling of secrets in CI/CD pipelines, mentioning tools like HashiCorp Vault and platform-specific secret management solutions. Additionally, it covers deployment strategies like blue-green and canary deployments, explaining how they work and their benefits, especially in terms of rollback strategies for faulty deployments.

05:02

🚀 Deployment Strategies and Jenkins Management

This paragraph delves deeper into deployment strategies, focusing on blue-green and canary deployments. It provides a step-by-step explanation of the blue-green deployment process, including the use of load balancers to switch between versions and a grace period for users. The canary deployment strategy is also explained, detailing how traffic is gradually shifted to a new version while monitoring its performance. The paragraph also addresses the critical aspects of handling faulty deployments and the importance of having a rollback strategy in place. Lastly, it discusses Jenkins setup, backup, and scaling, providing insights into installation, predictive scaling for handling varying build numbers, and the importance of regular backups of the Jenkins environment.

10:04

📢 Closing Remarks and Invitation for Feedback

In the concluding paragraph, the speaker invites viewers to share any additional CI/CD interview questions they may have encountered, encouraging them to post in the comment section for further discussion. The speaker also reminds viewers to engage with the content by liking, commenting, sharing, and subscribing to the channel, signaling the end of the video with a friendly farewell.

Keywords

💡CI/CD

CI/CD stands for Continuous Integration and Continuous Delivery, which are practices in software development designed to improve the process of integrating changes from multiple contributors into a single software project. In the video, CI/CD is the central theme, with the speaker discussing interview questions related to CI/CD setups, tools, and strategies. The script mentions the use of GitHub and Jenkins as part of a CI/CD pipeline, highlighting the importance of these practices in modern software development.

💡Jenkins

Jenkins is an open-source automation server that facilitates the automation of parts of the software development process, including continuous integration. In the script, Jenkins is used as an example of a CI tool that can be part of a CI/CD setup, with the speaker discussing how to handle Jenkins pipelines, secrets management, and scaling up Jenkins instances.

💡GitHub

GitHub is a web-based platform for version control and collaboration used by developers to manage and host their Git repositories. The script mentions GitHub as a part of the CI/CD setup, where it is used in conjunction with Jenkins to trigger CI pipelines upon each commit, illustrating the integration of version control with automation tools.

💡Secrets Management

Secrets Management refers to the process of securely handling sensitive information such as passwords, API keys, and other credentials throughout the software development process. In the video script, the speaker emphasizes the importance of explaining how secrets are handled in CI/CD pipelines, mentioning tools like HashiCorp Vault and cloud provider services like AWS Systems Manager and Azure Vault.

💡Deployment Strategy

A deployment strategy outlines the approach taken to release software updates or new features to production. The script discusses common strategies like Blue-Green deployment and Canary deployment, explaining their use in managing the release process and ensuring high availability and minimal downtime.

💡Blue-Green Deployment

Blue-Green Deployment is a method of deploying software in which two identical production environments ('blue' and 'green') are used. The script explains this concept as a way to reduce downtime and risk by running two production environments that are switched, allowing for easy rollback if the new deployment has issues.

💡Canary Deployment

Canary Deployment is a strategy that involves rolling out changes to a small subset of users before making the change available to everybody. The script describes this method as a way to test new application versions with a limited user base before a full rollout, helping to identify and mitigate potential issues.

💡Rollback Strategy

A rollback strategy is a plan for reverting to a previous version of an application or system in the event of a failure or issue with a new deployment. The script mentions the importance of having a rollback strategy, especially in the context of CI/CD, to ensure that any issues can be quickly addressed.

💡Auto Scaling

Auto Scaling is a feature provided by cloud providers that automatically adjusts the amount of computational resources allocated to a service based on the demand. In the script, the speaker discusses the use of auto scaling with Jenkins on AWS, explaining how it can be used to handle varying build loads efficiently.

💡Predictive Scaling

Predictive Scaling is a type of auto scaling that uses predictive analytics to anticipate changes in demand and adjust resources accordingly. The script refers to predictive scaling on AWS Auto Scaling, which helps in preparing for expected increases or decreases in traffic, ensuring optimal resource utilization.

💡Docker

Docker is a platform that uses containerization technology to simplify the deployment of applications. The script briefly mentions Docker as a method for setting up Jenkins, indicating its use in creating isolated and portable environments for CI/CD tools.

Highlights

Introduction of the top 5 most common CI/CD interview questions and their answers.

Explanation of the importance of detailing one's CI/CD setup in an interview.

Description of a typical CI/CD setup using GitHub and Jenkins with web hooks.

Discussion on the various stages of a Jenkins pipeline, including build, test, and deployment stages.

Emphasis on the significance of handling secrets in CI/CD pipelines and different methods to secure them.

Mention of tools like AWS Systems Manager, Azure Vault, and HashiCorp Vault for secret management.

Clarification on the difference between CI and CD, and the importance of being prepared for CD-related questions.

Explanation of popular deployment strategies like Blue-Green and Canary deployments.

Description of the Blue-Green deployment process with a focus on its rollback capabilities.

Overview of the Canary deployment strategy and its incremental traffic shifting approach.

Advice on how to handle faulty deployments or security vulnerabilities post-deployment.

Discussion on Jenkins setup, backup, and scaling up processes and their importance.

Details on setting up Jenkins on AWS with auto-scaling groups and predictive scaling.

Explanation of the process for taking backups of Jenkins using the .Jenkins folder.

Invitation for viewers to share other popular CI/CD interview questions in the comments.

Encouragement for viewers to like, comment, share, and subscribe to the channel.

Transcripts

hi hello everyone welcome back to my

channel and today we will talk about

what are the top 5 most uh cacd

interview questions and their answers

we'll try to answer these questions more

on the basis of some scenarios so let's

quickly uh jump into the questions and

see their answers as well so the first

one is explain your current cicd setup I

think this question can be asked in

multiple ways like people ask you what

is your cicd tooling what are the tools

that you're using or what TCI CD

according to you

is

established in your organization so

whatever it is uh the answer to it has

to be very elaborate because this

question basically uh gives you gives

the interviewer a chance to analyze your

knowledge on cicd so tell the answer in

a most detailed way so that uh he or she

can understand uh your expertise on cicd

so basically I have written the answer

here you can probably I mean I'll not

read everything here you can go through

the answer but uh generally you can say

cicd is continuous integration and

continuous delivery and in the current

organization we are using GitHub and we

are using Jenkins for the continuous

integration where we have set up web

hook which Triggers on each and every

commit that is made to GitHub and

triggers a CI Pipeline on Jenkins and

then you can talk about multiple stages

that are in your Jenkins pipeline like

you can say you have a build stage you

have test stage you have deploy stage

and you know whenever you're talking

about these things uh basically detail

them uh like how what is your build

stage what what are the different things

that are in your build Stay like static

code analysis unit testing building and

then in your test stage uh whether

you're doing smoke testing or you're

doing functional testing in your

deployment staging in your deployment

stage basically explain uh what is your

artifactory how you're building your

Docker image or application uh archive

whatever whatever you are building and

then explain how you are deploying it

onto your kubernetes cluster or

websphere weblogic application servers

whatever your end Target cluster is

so this is about your CI CD setup and

the process and the second question I

think this is a very important question

how do you handle Secrets because mostly

people will be very prepared for the

first answer first question uh the cicd

process and everything but you need to

explain how do you handle Secrets

because secrets are integral part of

every application these days right so

whether your SSH Keys whether your API

key whether it can be your you know

kubernetes login secret or anything you

deal with a lot of Secrets these days in

your cicd pipelines so basically answer

this question depending upon where your

Jenkins or any CI tool is set up let's

say you are on GitHub right so GitHub

provides an option for securing your

secrets in the cacd uh

in the action cicd itself if you're on

gitlab there is again there is an option

for uh securing your secrets in the ca

variables itself uh on your on your

gitlab UI apart from that let's say

you're on uh cloud provider like AWS so

probably you can say you store your

secrets in AWS systems manager and

retrieve whenever it is required or if

you're on Azure you are probably using

Azure Vault and one of the popular tools

uh irrespective of the cloud or anything

that you are in a hashic or vault so

hashicorp called Vault is one of the

most used uh applications for securing

storing your secrets

so be prepared with this answer because

this is one of the most asked interview

question for cicd

after that people ask about your

deployment strategy what I have uh seen

most of the times is most of the times

is that people are very prepared with

respect to the continuous integration CI

part but uh not with the CD The

Continuous delivery but you know uh CI

is very easy to set up as well you have

tools like Jenkins GitHub actions it's

very easy to do uh CA but coming to CD

you have to be uh

very uh you know um

keen on how you are setting your CD what

is your type of application where you

are deploying your application onto so

continuous delivery is uh a key uh

component for uh your entire cacd as

well as during your interviews people

ask a lot about CD so coming to the

deployment strategy you can talk about

the popular deployment strategies if you

have employed either blue green

deployment or Canary deployment on your

uh site on your organization so

depending upon what you have set up

probably answer these things but uh to

explain what is blue green and what is

Canary in a very short way so blue green

deployment is basically where uh if you

see the picture onto the left side you

know using blue green deployment what to

do is that you already have an

application let's say the application

version is 34 and you are deploying a

new version of your application probably

call it 35 okay so firstly what you do

is that

you point your load balancer to the

application 34 which is deployed on your

cluster then you install uh application

35 on the same cluster the new version

using your cicd pipeline and what you do

is that you shift your load balancer to

the application certified and so that

no uh traffic is sent to the application

34 however you provide some grace period

Grace time for the users that are

already on application 34 and once this

grace period is over you simply Point

your load balancer I mean you already

pointed your application load balancer

to 35 you just delete application 34.

once you are confident about your

application testing and everything

okay so this is the process using blue

green deployment now the other popular

deployment strategy is the canary

deployment strategy and using Canary

what you do is that basically you shift

in the same way you deploy both

application 34 and 35 but instead of

directly pointer load balancer to

application 35 what you do is that you

limit your traffic to application 35

initially you send only 10 percent of

your traffic so all this modern day load

balances like F5 or nginx or any load

balancer using Ingress they are able to

do it uh by you know they call it ratio

based uh

ratio based load balancing or weight

based load balancing whatever it is so

uh initially route only 10 and then

probably you can switch the gears 66.33

and then finally you can do 30 so there

are very lot of I mean there are a lot

of tools which can achieve this uh for

the canary deployment model uh if you

want to learn about uh

Kennedy deployment probably you can

Google for Kennedy deployment and tools

can be used to achieve the canary

deployment but all the popular load

balancer can do it these days

now what do you do if the deployed

application is faulty or let's say your

application has security vulnerabilities

or your application is faulty it's not

working as expected so what do you do

one of the most easy ways to answer this

is uh talk about the blue green

deployment which we talked in the

previous slide because if you look here

carefully uh if something goes wrong

with your blue green deployment what you

can immediately do is that point your

load balancer from 35 to 34 or people uh

basically do it using multiple sites

right so blue site and green side and if

something goes wrong they immediately

appoint the load balancer to the green

uh from Green side to the blue side so

this is the most easy way blue green

deployment but if you are employing any

other deployment strategies you have to

be very careful on explaining how did

you roll how do you actually roll back

but blue green is the most easy way to

roll back so this question uh the way

you answer is when something goes wrong

we have a rollback pipeline or we have a

strategy for rollback uh because we are

doing blue green deployment it is very

easy for us to roll back

finally uh

Jenkins setup backup and scaling up so

how do you do this the reason why I put

this question only related to Jenkins is

that I recently

set up a poll on my YouTube channel

asking what is the most popular CI tool

that you are using 90 of the people

choose Jenkins only 10 of them choose

GitHub actions gitlab and Travis I think

nobody has actually opted for it so the

reason for me to talk about Jenkins in

this specific question is because of

that so this is again important question

because uh apart from setting up your

cicd pipelines it is always important

for you to understand how your CI tool

or gen for that

for this question Jenkins however

Jenkins is set up how do you uh take

backups for your Jenkins uh logs or

bills or artifacts anything and then how

do you scale up because you know at

times you might get more number of bills

at times you get less builds so scaling

up scale down is also one of the

interesting aspects

so it's very easy to do with Jenkins uh

I think Jenkins installation is the most

easiest thing uh you just have in uh you

can do it through Docker as well you

have a simple curl command that you can

use to install Jenkins I can show you uh

some other time how do you install

Jenkins it you can I mean nobody will

actually care about the installation

because it's just a single command but

the most important thing is a backup as

well as scaling up so for scaling up I

would say one of the

I'll take an example let's say your

Jenkins is on AWS what you can say is

that uh Jenkins is set up on AWS and we

have set up Jenkins uh on easy to

instance and we have set up an auto

scaling group so this Auto scaling group

basically takes care of scaling up

scaling down we have employed the

predictive scaling uh on the AWS Auto

scaling so predictive scaling basically

uh takes care it basically predicts like

at this time you might get more traffic

at the time you might get less traffic

so it will it will automatically scale

up an ec2 instance and once the ec2

instance is spinned up Jenkins basically

uses SSH

to interact with the newly created node

so this is the process and for backup I

think Jenkins has a DOT backup folder if

you can sorry dot Jenkins folder just

backup the dot Jenkins periodically

using some prawn jobs and that will

basically take your Jenkins backups so

uh this is the top five in cacd

interview questions that I have for you

and uh if you feel that I missed

something or there are other popular

interview questions uh related to cicd

please post them in the comment section

and I'll be more than happy to answer as

usual don't forget to like comment share

and subscribe to my channel thanks I'll

see you in the next video bye