DevOps Interview Questions (Part 1) | Ace DevOps Interview with These 2024 Q&A - StarAgile

[Music] hello everyone welcome to the star agile YouTube channel I'm sonal Mel and I work with star agile and conduct various trainings on devops we provide training also On devops Tools like anible Docker kubernetes junkins and monitoring tools today we will be discussing about the devops interview questions and answers for fres as well as for working professional but before we move ahead please click on uh the Subscribe button and join us on this exciting journey to master devops what better than learning devops with the help of question and answers here I present to you the

top most interview questions that you will come across during interviews the very first and the popular interview question that we have are the various tools that you have worked about in devops you know that devops is not a pro programming language it is not a a a theory it is not about uh team devops is a methodology devops is a process devops is all about automating your sdlc process so when I talk about the sdlc process there are various phases in it and each phase can be automated with help of a devops tool let us

have a quick look at it so let us quickly draw an sdlc phases so the very first phase that we look at is planning but as a devops engineer we may not concentrate much on the planning phase the first phase that we want to work with is the coding phase once the requirements given by the client are frozen it is these requirements are shared with the ID team members who will then convert the semiformal language written requirements into a program or a code into a working application the put is a source code that you see

on my screen and to manage and maintain this source code we make use of tools like git GitHub bit bucket git lab TFS code commit and so on now one of the major principle of devops is communication and collaboration so multiple team members will write the source code and collaborate together on these Version Control platforms which are GitHub bitbucket and so on some of them are Community version as well as there is Enterprise version of the tools also available the next phase that comes in the sdlc is your build phase and that is automated via

the tools which is Jenkins you have Travis you have bamboo you have gitlab cicd pipelines Azure pipelines AWS pipelines and so on right the build is a process where we come compile the code we test the code we package the code into an artifa whenever we have to deploy the code this package is deployed onto the servers build process can be automated with help of the integration tools that you see on my screen however build process is automated via the build tools like M and Gradle Ms build Pi Builder and so on those tools are

used manually by the developers as a develop engineer we are supposed to automate these tools we are supposed to automate the process of build with help of genkins where we create the cicd pipelines after the build process is completed we have the process of integration testing or n2n testing so for which you can take we can also call it as a functional testing for which we can use tools like selenium you have cucumber you have tools like uh as part of selenium there are major other testing tools that can be included for now we'll Target

selenium you have qtp also which can be used as a functional testing tool after this we will go ahead and we'll deploy the code in order to deploy the code you can deploy the code manually but we are talking about devops so we use deployment tools like Docker kubernetes which supports continuous deployment and anible which also supports deployment on Virtual servers so I'll list down over here so if you want to deploy on Virtual servers you make use of anible if you want to deploy on containers then you make use of Docker if you want

to go with continuous deployment which we will talk in the upcoming questions what is continuous deployment we're going to discuss that you make use of the tool kubernets in order to deploy our applications on a server the server should be provisioned in a Design Network in the desired setup right only then the server will be up and running now provisioning of the infrastructure plays a very important role when we are deploying our applications so that comes as part of the next phase now I always tell the operations phase can be interchanged with the deployment if

your servers are not set up your envirment is not ready then your operation stage comes first where you provision the infrastructure why the tools like terraform or cloud formation or anible also can be used for configuration management configuration management and infrastructure setup right and then later you can deploy your code after the operations is done after the deployment of the code is done the final step is to maintain the code to manage and ensure that your code is reliable and your application is always available to the end users so hence we add the step called

as monitoring in monitoring you can make use of several tools starting with nagus elk stack Prometheus grafana data dog and many more right so here is your automated sdlc where you first collaborate the code over a Version Control tool like GitHub you build the code with help of Jenkins and M or if it is a python code we will build with piy Builder if it is a net code we will build with Ms build then we perform the functional testing where genkins will pick up the automation test cases and test it like selenium can be

used here qtp can be used here then we deploy the code deployment is a process of pushing your build on the desired servers if you have to set up your servers you make use of the tools like terraform and cloud formation and finally monitor your applications so this is how you can explain the various tools that you have worked on in your devops so this covers my first question and here is further explanation to what is cicd so cicd stands for continuous integration and continuous deployment let me explain you continuous integration first with help of

a diagram and then continuous deployment let's go ahead and look at it so we'll continue with the same sdlc process let us consider that a developer pushes the code into so I have a developer who writes the code for a given requirement and he will be pushing the code into GitHub so we have the source code let us say Java based code or python code or your HTML code any code is available on your GitHub repository where multiple team members are collaborating the code great once the code is available we need to compile the code

we need to test the code we need to package the code this process is called as the build process the process of packaging the source code that involves compiling testing the code unit testing the code and packaging it's called as the build process now traditional models included the build process from the very beginning but it was performed manually with help of tools like M and Gradle you will have net for C or dot uh you have MS build for them and then you make use of P Builder if you have to build python code after

this we will build the code manually but with devops we want to automate this process of building the code to automate the process we make use of a tool like genkins or you can use cicd tools on Azure or AWS or a gitlab cicd runner can also be used latest tools that we use is a GitHub actions also can be used for this process where tools let us consider our tool as Jenkins so Jenkins is also called as an orchestrator a continuous integration server an automation server or an orchestration orchestrator which is responsible to pick

up the code to pick up the code from GitHub and ask the build tool maven to go ahead and build it so here Jenkins acts like a collector so as the developer pushes the code so we're talking about first integration and integration is a process where an automation tool like Jenkins integrates with GitHub to fetch the code fetch the code and genkins as a tool integrates with build tool to build the the code package the code right so there are two integrating activities that are happening fetching the code and packaging the okay now we want

to do it continuously so jenin supports automation triggers triggers which when applied on genkins can sense the change that has happened on that has happened on GitHub so let's say a developer pushes the Cod at 9900 a.m. that is he commits the cod in get up as soon as the code is available on GitHub Jenkins will sense the change it is also called in real time as a event based pip planine Jenkins will sense the change pull the pull the required code and package it by by the tool like M or and gra right so

here in genkins implementation of triggers supports continuous integration continuous integration is a process of picking up the code from GitHub and compiling it and testing and packaging the latest code shared by the developer now in case there is a negative impact also in case there is an error while compiling the code or packaging the code Jenkins is a tool notifies the developers gen Cas as a tool notifies the developer to fix the code developers will fix the code push the new code Jenkins will sense the change and again Ask the build tool to compile package

once the package is available genkins will integrate with artifactory to push the artifact on the registry like artifact like jrog artifact Ries Nexus artifact Ries or Registries over the cloud can be used to maintain the artifacts so that is your continuous integration process now in once the artifact is available let me also list down here once the artifact is available let's say in the artifactory it is available the next step is to deploy the code now to deploy the code we need let's say three environments are available we generally have the test environment staging environment

and then finally we have the production envirment so there are two parts when we talk about CD CD can be continuous delivery can be continuous deployment so when I talk about continuous delivery so here we're talking about the QA environment test environment prepro environment you can call it as a staging environment you can call it as a user acceptance testing environment and a production okay now when we talk about QA over here so or we talk about continuous delivery first continuous delivery is a process where you use an automation tool that will take your build

and deploy it on the test envirment so the output of the build phase was let us say an application. War file okay this war file is automatically picked up by genkins and pushed that is copied or deployed on a qsl right and then here we perform testing testing that can be performed via automation tools genkins which will pick up the selenium code from GitHub execute the test cases in case of any issues the application is not working we report it to develop ERS via the email or via slack notification then the developers fixes the code

a new build is generated and deployed in the test en if testing goes fine using an automation tool to deploy the code onto the preo envir so the successful build the tested build is then pushed into the prepro environment okay here once it is pushed into the prepro environment we perform performance testing loow testing is performed here using tools like jmeter low D and finally once the acceptance testing is completed we will stop deploying of the application via a tool into the production so continuous delivery is a process where an automation tool will deploy in

QA and prepro however deployment to the production environment is performed manually by getting a approvals from the stakeholders and on a given date and a time we will deploy the code into the production manually we will run the commands to push the coding however when we talk about continuous delivery which develops support we use an automation tool to immediately deploy the application over the production server also so all the e-commerce applications that you see they all support continuous deployment process where as the code is written code is built immediately tested via the automation tools and

then pushed to the production andv work that is why nowadays you see what you request is immediately available in few hours or sometimes even in few minutes because of continuous deployment so this covers my second question which is cicd continuous integration where developers regularly merge the code and the build automation tool continuous integration tool like Jenkins frequently pick ups the code and builds a continuous delivery process where you are manually deploying into the production environment a deployment process where your application goes live within few minutes or within few hours instead of days continuous deployment great

now here are some of the benefits of devops this also summarizes my first two questions so when you working with devops you are making use of various tools so since we are working with various tools like GitHub genkins build tools testing tools deployment tools are implementation of sdlc is much faster and since a tool is used there will be less human errors previously with deployments there were many if any command is missed if any file is missed our deployments would fail but nowadays because of autom deployment especially with containerized applications the chances of failures are

less that supports zero downtime to the end users because of continuous integration the quality of the code is very good that is going to the end users right so these are some of the main benefits also in traditional models we had less collaborations and communication between the development and the operations team so devop support communication there are development team and operations team work together right in order to deploy the code immediately and there are less failures because of tools used and faster deployment scalability because we are using automation tools like terraform cloud formation it allows

us to scale up the infrastructure at a very faster rate when compared to the traditional models so what what are the best practices in continuous integration so as we discussed uh so I'll quickly show you why the tool itself we discussed frequent build frequent comit so on the GitHub let me show you the tool so here I have opened a GitHub repository so as I told you there is an automation tool GitHub actions also so here I have written a code I'll show you a code in a minute so this repository our developers have provided

some source code so as a developer will commit into into this repository immediately The Continuous integration tool will pick up the code so I've written some code here I'll quickly show you which is using the tool called as GitHub actions do you see actions on the GitHub repository it is also the latest continuous integration tool so the GitHub actions allows us to implement cicd process where you tell on which branch do you want to uh perform The Continuous integration then here you will make use of the tools let me scroll down okay so here it

is making use of the uh tools like M to build the code and Docker to deploy now you may also try to see it in genkins I have some pipelines over here continuous integration pipeline let me quickly log in so this is another tool which is genkins which also supports continuous integration inside this tool so you can see a pipeline here a beautiful pipeline is visible where we are having the first step of cloning the repository so the question says is what are the best practices of continuous integration the best practices are first and foremost

you writing the code in order to perform continuous integration so when we writing the code the process is much faster okay so the code code involves fetching the code compiling the code testing the code and packaging writing the code is very easy in the continuous integration tool like genkins second step is you can integrate genkins with help with email notification like if you see in this particular tool let's say I'm generating reports and I want to send that report to my team members so one another advantage of using integration tool is I can integrate generate

the tool give it a movement for it to start and I can send notifications via email so let's give it a moment to start in the post build steps we can add a step so this report needs to be sent so we can add email notification so we can send we can add recipients to to whom we can send emails whether our job is passed or failed and we can also attach the report with it that is second uh benefit of using a continuous integration tool the third benefit is you can of course do continuous

testing also deployment also we can do with this tool in addition to this you can also integrate with the Version Control tool right and I also like some of the features of genkins or any integration tool is it supports multiple people to work at the same time right it also integrates with thousands other tools giving you automation at a very high level it also allows you to ensure High availability of your servers you can work with the setup of clouds right where you it can help you to scale up your genkin server or help you

to scale up the servers where you want to deploy your pH you can also integrate Jenkins with other virtual servers to distribute the workload so the are some of the important features of genkins so when you inform or when you attend an interview on continuous integration question being asked to you then some of the advantages of continuous integration is of course a faster build higher quality continuous uh uh testing reports will get generated plus you can send notifications to different team members now here is a theoretical question where you can explain with help of the

example of what is the difference between devops and agile so agile when extended to the operation steam forms devops so if you see in this diagram over here agile is a process where you break down your requirements into small small user stories these user stories are then developed tested and reviewed a demonstration is given to the client upon his feedback we make changes and complete the Sprint so agile is a process of incremental development it's a development model unfortunately you don't deploy immediately just a you don't deploy immediately you may deploy fourth nightly or monthly

or three months deployment you may have however in agile there is a communication between the developers and testers they are working closely to deploy to develop the code at a faster rate however deployment is done on a given fixed date and time but when we talk about devops it overcomes the challenges of aile and it extends the communication with the operations team the development testing and operations team work together to automate the sdlc at to deliver an application at a faster rate devops is coined from two terms development plus operations right and it's all about

automation it's all about automating your workflows for monitoring and making your application available to the end users okay so agile focuses on development devops focuses on faster deployment it's a deployment model now here are a question which is inclined towards genkins so what are the various Security Options that we have in genkins so genkins is a secure tool of course you need to add some more actions inside Jenkins to make it more secure like SSL certificate can be added uh ensuring it is highly available then in addition to this Jenkins comes with its own inbuilt

security feature let me show you over there if you go to the Jenkins dashboard and go to manage Jenkins over there you have security part in the security you can create multiple users in genkins and we can give credentials to them uh so there will be a secure access to the each team member in addition to this the use users also have role based access like you can provide them roles or metrics based access we call them in Jenkins in this case we can give read only access read and write access to the jobs they

can create jobs delete jobs or only view the jobs so that security part is taken care in this section making genkin secure here there are three different types of authorizations so first and foremost security realm is a pro is a component of Jenkins where we will see Jenkins is storing its data inside its own database okay you can also connect jenin server to Elda which is commonly used in real time for maintaining the user database but by default Jenkins uses its own database in the Jenkins default directory where lip Jenkins okay when you look at

the authorization part we have one 1 2 3 five types of security settings in Jenkins now if you said this that means uh you don't need to log in anybody who has the IP address and port number of Jenkins server can do anything on Jenkins which is risky we don't select this then legacy mode is also not selected it is just an access to the Legacy project now these three are important security settings that you can do the default setting that we have is a loged users can do anything so this is the default setting

as you log in as an admin user or as a Tom user or Allis user whatever is your user ID and password you can login and perform the activities but in general I would not give entire access to every user only admin will have the complete access so we will go with metrics based security so when I talk about metrics based security then I can add a user like let's say I add admin user to admin user I can give complete admin access that it can do anything or let's say I to this user I

give he can create jobs he can read the jobs he can move the jobs then he can create an agent he can delete agent is nothing but a distributed environment of genk kids a server then you can create credentials or sometimes to a user I may give only read access he can only see Jenkin server he cannot make any changes to it so this is called as metrics based security Security based on the role then we have Project based security so Project based security that means on that particular job the user has an access so

you can give an overall access as let's say admin user overall access let me actually not give it to admin because admin should have complete access okay so one user should have complete access I'll create one more user let me see if I have the user so you can create a user here let's say I'm creating a user allice I'm providing credentials to the user allice now I'll give permissions to this user so we will look at managen kins security Project based secur when I go to Project based security the admin user is having all

access which you should give otherwise you will have to reset the settings of Jenkins then we will go with ILS user that I have just created to ILS I'm giving read access that means on my machine or on This jenin Server when Al is connect she will be able to only see the jobs she cannot edit the job she cannot delete the job she cannot execute the jobs however one job I'll give her full access so that is project in genkins Project means job metrics means read axis write axis what is the access we are

do so here I will give dashboard I'll take a job let's say I take uh continuous integration Pipeline and I go to configure and you will see an option of Project based security enable Project based security First Option here we can add Alice user and I'll give her full access she can add manage credentials on Jenkins she can create jobs on Jenkins and only this particular job she can only work with this particular job that's all so I'm giving complete access to this job and I save it okay now if I log out I'm currently

logged in as administrator I will log out and log in as Alex now can you see she is only able to see only the job to which I have given her access rest all she doesn't have access to manage genkins she cannot create a job but she can work with this job she can build the job she can configure the job she can delete this pipeline everything okay so this way we can give restricted access to the users on CH isn't it so this and admin user however has complete access this is the answer to

your next question which is what are the different types of security settings that we have in general that is role based access authentication authorization secrets that you can maintain and security plugins now what are the different devops life cycle I think we have just discussed sometime back the various stages of devops that can be automated in the sdlc so first is the planning phase in the planning phase the developer the client team and the business analyst team will collect and freeze the requirements once the requirements have been frozen once the requirements have been frozen these

requirements can be broken down into small small user stories and then for which these user stories are shared with the developers developers will start writing the code using high level programming languages like python Rubik dcsh and so on Java JavaScript and net after the code has been written the code has to be tested to verify and validate that the code is working so we test the code and package Now package is a process package is a process where you will convert the code into a machine understandable like your servers cannot understand Java they understand zeros

and ones so build is a process where you compile the code convert it into a machine understandable code and package into an artific that can be deployed then we write automation test cases using selenium or qtp then we have the process of releasing the code to the deploy so the build phase once completed is also called as make a release phase where your code is ready to be deployed then we make use of the deployment tools like anel or papet or Chef or docker uh gitops is used cicd pipelines are used to deploy the code

to the production finally you also ensure that your servers are up and running and your servers are having the desired softwares and packages that are needed for your application to run so operation stage involves infrastructure setup and maintaining the servers by doing the configuration changes then finally we monitor the code monitor the applications get the feedback and fix it at every stage you can add a security testing tool making it as a death secops life cycle also which we will cover in the upcoming questions okay now coming to the topic of what is configuration Management

in detail we will discuss let me try to explain your configuration management with the help of a example so let's take a quick slide let us say you have 100 servers let's say you have 100 servers on this servers you want to install a package called as tag then you have a package or a software called as St then you have 100 servers on which we have to create a database let's say employ now if I ask you to connect to these 100 servers and install Tom Tag connect to these 100 servers one by one

and create a database would you want to create it would you want to do it manually connecting to all the 100 servers of course not we would not want to do it manually it is time consuming it is a repetitive task I may make an earth some servers I may miss so what we do traditionally we would write shell scripts shell scripts that will connect to the servers and will execute the script on we will copy the script on it we will connect to the server we will copy the script on it we will see

what is the operating system corresponding script will be copied we will check whether tomat is present and then we will install Tom we will create a database if the database is not but that's again taking lot of time if on one server I'm taking five minutes so on 100 servers I will take 500 minutes to complete which is a tedious job and I don't want to do it mom so here devop supports automation tools for configuration man first configuration what is configuration connecting to various servers to make some change connecting to various servers to install

a package to copy a file to deploy an application is called as configuration management is configuration now doing it manually with help or perform doing it automatically via a tool is called as configuration management so there is configuration management which can be done manually there is configuration management which can be done automatically with help of tools so that is what we are going to see with devops so using a tool like anel puppet or Chef configuration manage let's talk about anible so anible is an automation tool where you can write the code as part of

this code anible will easily connect to hundreds of server in few seconds and install the desired package so anible Chef Sal stack these are examples of configuration management tools that connect to the Ava able infrastructure and automatically parall connect to them or sequentially connect to them one after the other and do the desired changes right the and also the main task of configuration management tool is to ensure the desired changes are always aware so there are two things desired changes and current changes tools like anable will ensure the desire changes are always available if the

desire changes are not they immed immediately they will run the code to make the systems as required by the environment for deploying the application so that's about your configuration management which maintains the important point is consistency all the environments in the real time all the environments in the real time requires consistency like test environment you have your production environment you have your prepro environment it requires that your servers are up to date and have the same application right have the same code running on so that consistency can come with the help of configuration management so

I hope we will stop here now I hope you found this video on devops interview questions insightful we are preparing more questions for you as part as part two so don't forget to subscribe our Channel stay tuned and we will see you soon thank you so much let's look at the next two questions which are related with each other which is what do you mean by configuration management and what is it that you mean by infrastructure as a code so I would like to explain you with help of an example let me open a pain

slide to explain assume a scenario where you have an environment in real time we have Dev environment test environment production environment environments are nothing but set of servers where your application is running so assume your environment has 100 servers and our main goal is that these servers should have same setup consistency is the term that I'm looking forward to that I'm looking at so consistency or making your environment same across test production and DEP so let's say I have 100 servers where I want to install a package down let's say there are 50 servers on

which we want to copy a configuration file so here is my question would you want to connect to the 100 servers manually and check if tomat is present if it is not present install Tom or connect to these 50 servers and copy the configuration file would you want to do it manually of course not it's a tedious job time consuming so immediately you will say son we shall write a script for yes if you're good at Shell scripting you can manage Linux platforms you can write scripts for separately for sento red hat or for ubu

yes you can write shells but in that case also you need to copy the script execute on each of the Ser so there is a manual task involved so writing scripts and managing them is an obsolute job with devops coming into play we can automate this process process of configuration management so configuration is a term where you are connecting to multiple servers to make changes on the servers and to bring all the servers at the same level that is consistency across the envir management manually or automatic manage the configurations by manually connecting to the servers

or using an automation tool so with devops we perform configuration management with the help of tools so if you make use of a tool like Anil puppet Chef Sal stack any such tool can be chosen cicd on GI lab also you have a process of implementing configuration management GitHub actions also provides you a feature of creating the infrastructure installing the required packages and then integrating and deploying the applications so various tools are available I'll pick up a tool answerable where you can write the code code is written in a very simple language yamel we write

playbooks in the playbooks I determine or I declare the desired changes that I want to do on this servers answerable as a tool will parall or sequentially connect to all these servers within few seconds the changes will be available that's the power of automation now when we talk about configuration management tool or any tool there are two parts desired changes that you want and the current changes so anible puppet or Chef or Sal stack any tool you take they always try to maintain the desired changes on the servers but before we make changes to the

servers the servers have to be made available in the environment we need to provision the servers hence the term provisioner comes into PCT so another part which is my second question what is infrastructure as a so using an automation tool to write the code and provision your infrastructure is called as infrastructure as a so before we look at configuration management first look at what is infrastructure as a infrastructure is nothing but your servers right your databases your network your subnet your security groups your autoscalers your load Balan or Dynamo DBS S3 bucket storage all of

these constitutes to be your infrastructure a set of servers where your application will so we can manually create it or use an automation tool so using a tool like terraform where we write the code to connect to the required cloud provider or your virtual uh you know if infrastructure is in promise or uh any virtual server so use terraform supports virtual uh connecting to the virtual servers also you can check the registry of terraform however mostly you will see implementation of terraform on the cloud so the interview question is basically what is infrastructure as a

ke so the plain and simple answer to that is writing the code to provision an infrastructure on the available Cloud using the tool like terraform or cloud formation is called as infrastructure ASM once the servers that that is your infrastructure is available using an automation tool like anel or puppet or ship to execute the code that will make changes on the server for the desired deployment and configuration is called as configuration manager so you have configuration management and you have infrastructure as a infra structure as a code right it's very very popular tool nowadays and

there is a terraform certification that you should uh Target to do isn't it and as part of the courses also you can learn terraform and master it which is really popular tool so that's the answer to your question what is infrastructure as a code tool so here uh you will see a simple code which is written infrastructure is a practice where you're provisioning so there is a term called as provision Prov Vision that means create modify or delete your servers on the cloud platform so here there is a simple code written of terraform where you

are creating an ec2 instance of the desired operating system Ami stand for Amazon machine image of the desired instance type configuration of 1 GB and uh one CP code and this is the name of this it's a small quote snippet to demonstrate on how infrastructure as a code Works to automate the process of infrastructure creation so I will stop here in the upcoming session we will see a quick demo on how infrastructure as a code can be provisioned with the help of terraform we will be looking at more questions uh in the upcoming sessions so

I hope you enjoyed this session and you found it very insightful we are preparing lot of questions for you that will help you to clear interviews so please don't forget to subscribe our Channel and stay tuned for uh for new questions upcoming thank you so much I'll see you soon bye-bye [Music]