40+ Cloud Devops Engineer Interview Questions and Answers

Different types of EC2 instances based on costs include On-Demand Instances, Reserved Instances, and Spot Instances.

• On-Demand Instances: Pay for compute capacity by the hour or second with no long-term commitments.

• Reserved Instances: Reserved capacity for 1 or 3 years, offering significant discounts compared to On-Demand pricing.

• Spot Instances: Bid on spare Amazon EC2 computing capacity, often available at a fraction of the cost of On-Demand instances.

The command to import a pre-exported Docker image into another Docker host is 'docker load'.

• Use the 'docker load' command followed by the file path of the exported image to import it into the new Docker host.

• For example, 'docker load < exported_image.tar' will import the image from the file 'exported_image.tar'.

Ansible is an open-source automation tool used for configuration management, application deployment, and task automation.

• Ansible uses YAML syntax to write playbooks

• Playbooks contain a set of tasks to be executed on remote hosts

• Ansible uses SSH protocol to connect and execute tasks on remote hosts

• Playbooks can be used for various tasks such as installing packages, configuring services, and managing users

• Example playbook: - name: Install Apache hosts: webserver become: true tas...read more

CMD specifies the default command to run when a container is started, while ENTRYPOINT specifies the executable to run when the container starts.

• CMD can be overridden at runtime by passing arguments to docker run command

• ENTRYPOINT cannot be overridden at runtime, but arguments can be passed to it using docker run command

• CMD is often used for specifying the main application to run in the container

• ENTRYPOINT is commonly used for defining the executable that runs the main applic...read more

The lifecycle of a Docker container involves creation, running, pausing, stopping, and deletion.

• Creation: Docker container is created from an image using 'docker run' command.

• Running: Container is started and runs the specified application or service.

• Pausing: Container can be paused using 'docker pause' command to temporarily stop its processes.

• Stopping: Container can be stopped using 'docker stop' command, which halts its processes.

• Deletion: Container is removed using 'docke...read more

Amazon EC2 is a web service that provides resizable compute capacity in the cloud.

• Amazon EC2 stands for Elastic Compute Cloud

• It allows users to rent virtual servers on which to run their own applications

• Users can choose from a variety of instance types with different CPU, memory, storage, and networking capacities

• EC2 instances can be easily scaled up or down based on demand

• Users only pay for the compute capacity they actually use

Git stash is a command in Git that temporarily shelves changes you've made to your working directory.

• Git stash is used to save changes that are not ready to be committed yet.

• It allows you to switch branches without committing changes.

• You can apply the stashed changes later on using 'git stash apply'.

• You can list all stashed changes with 'git stash list'.

• You can remove stashed changes with 'git stash drop'.

CMD and ENTRYPOINT are used to define the default command to run in a container. ADD and COPY are used to add files to a container.

• CMD is used to specify the default command to run when a container is started. It can be overridden by passing a command to docker run.

• ENTRYPOINT is similar to CMD, but it is not overridden by passing a command to docker run. It is used to define the main command that should be run in the container.

• ADD and COPY are used to add files to a container...read more

Application Load Balancer and Network Load Balancer are two types of load balancers used in cloud computing.

• Application Load Balancer operates at the application layer and is used to distribute traffic to multiple targets based on the content of the request.

• Network Load Balancer operates at the transport layer and is used to distribute traffic to multiple targets based on IP protocol data.

• Application Load Balancer supports HTTP/HTTPS protocols and can route traffic based on U...read more

Jenkins is an open-source automation tool used for continuous integration and continuous delivery (CI/CD) pipelines.

• Jenkins is a popular tool in the DevOps ecosystem.

• It allows developers to automate the build, test, and deployment processes.

• CI/CD pipeline refers to the automated workflow of building, testing, and deploying software.

• Jenkins enables the creation and management of CI/CD pipelines.

• It integrates with version control systems like Git to trigger builds and deploymen...read more

Docker images are lightweight, standalone, executable packages that contain everything needed to run a piece of software.

• Docker images are built from Dockerfiles, which specify the environment and dependencies needed for the software to run.

• Images can be stored in Docker registries like Docker Hub for easy sharing and distribution.

• Containers are created from Docker images and run as isolated processes on a host machine.

• Docker images are layered, meaning they can be built on t...read more

The process involves packaging the application, transferring it to target servers, configuring the environment, and starting the application.

• Package the application into a deployable format (e.g. Docker image, WAR file)

• Transfer the packaged application to target servers using tools like Ansible, Jenkins, or manual SCP

• Configure the environment on target servers (e.g. setting up database connections, environment variables)

• Start the application on target servers and monitor for ...read more

Docker Namespaces are a feature in Docker that isolates containers from each other and the host system.

• Namespaces provide a way to isolate processes, network, and filesystem for containers.

• Examples of namespaces include PID (process IDs), NET (networking), and MNT (mount points).

• Each container runs in its own set of namespaces, providing a level of isolation and security.

Kubernetes is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications.

• Kubernetes is used to manage containerized applications across multiple hosts.

• It provides features like automatic scaling, self-healing, and rolling updates.

• To get a list of all pods, use the command 'kubectl get pods'.

• To delete multiple pods in one command line, use the command 'kubectl delete pods ...'.

Git rebase modifies the commit history while Git merge creates a new merge commit.

• Git rebase rewrites the commit history by moving the entire feature branch to the tip of the master branch

• Git merge creates a new merge commit that combines the changes from both branches

• Rebasing is useful for keeping a linear commit history while merging is useful for combining multiple branches

• Rebasing can cause conflicts if multiple developers are working on the same branch

• Merging can result ...read more

Jenkins pipeline automates the software delivery process by defining a set of steps and actions to be executed.

• Pipeline is defined using a Jenkinsfile

• Pipeline stages define the steps to be executed

• Pipeline can include parallel stages and conditional steps

• Pipeline can integrate with other tools like Git, Docker, and Kubernetes

AWS cloud is a secure and scalable cloud computing platform provided by Amazon Web Services.

• AWS cloud provides a wide range of services such as computing power, storage, databases, and networking.

• It allows businesses to quickly scale their infrastructure up or down based on demand.

• AWS cloud offers high availability, reliability, and security.

• It enables organizations to reduce costs by paying only for the resources they use.

• Examples of AWS cloud services include Amazon EC2, Am...read more

NodePort, Ingress, and LoadBalancer are Kubernetes services used for exposing applications externally.

• NodePort is a service that exposes an application on a static port on each node in the cluster.

• Ingress is a service that exposes HTTP and HTTPS routes from outside the cluster to services within the cluster.

• LoadBalancer is a service that exposes an application externally using a cloud provider's load balancer.

• NodePort and LoadBalancer services can be used with TCP and UDP pro...read more

One drawback of cloud is potential security risks and data privacy concerns.

• Security risks: Cloud services are vulnerable to cyber attacks and data breaches.

• Data privacy concerns: Users may have limited control over their data stored in the cloud.

• Dependency on internet connection: Cloud services require a stable internet connection for access and functionality.

• Cost: Cloud services can become expensive, especially for large-scale usage.

• Compliance issues: Some industries have s...read more

Cloud is important for data privacy as it provides secure storage, encryption, and access controls.

• Cloud providers offer advanced security measures to protect data from unauthorized access.

• Data stored in the cloud is encrypted, making it difficult for hackers to decipher.

• Cloud platforms allow for granular access controls, ensuring only authorized users can view or modify data.

• Regular security updates and patches are applied by cloud providers to protect against new threats.

• Cl...read more

VNET is a virtual network in Azure that allows resources to securely communicate. NSGs are network security groups that control inbound and outbound traffic.

• VNET stands for Virtual Network and is used to connect Azure resources together securely

• NSGs are Network Security Groups that act as a virtual firewall to control inbound and outbound traffic to Azure resources

• NSGs contain security rules that allow or deny traffic based on source and destination IP address, port, and prot...read more

Ansible playbooks are executed using the 'ansible-playbook' command in the terminal.

• Use the 'ansible-playbook' command followed by the playbook file name to execute a playbook.

• Specify the inventory file using the '-i' flag if it's not the default 'hosts' file.

• Use the '-e' flag to pass extra variables to the playbook if needed.

• View the playbook execution output for any errors or warnings.

• Example: ansible-playbook myplaybook.yml -i inventory_file -e 'var=value'

Cloud computing involves the delivery of computing services over the internet, including storage, databases, networking, software, and more.

• Cloud computing allows users to access resources on-demand without the need for physical infrastructure.

• It offers scalability, flexibility, and cost-efficiency compared to traditional on-premises solutions.

• Common cloud service models include Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS)...read more

Route 53 routing policies determine how traffic is routed to your resources.

• There are several routing policies available in Route 53, including simple, weighted, latency-based, geolocation-based, and failover.

• Simple routing policy sends traffic to a single resource.

• Weighted routing policy distributes traffic based on weights assigned to each resource.

• Latency-based routing policy sends traffic to the resource with the lowest latency.

• Geolocation-based routing policy sends traff...read more

To host a site in AWS, you can use services like Amazon S3, EC2, or Elastic Beanstalk.

• Use Amazon S3 for static website hosting

• Use Amazon EC2 for hosting dynamic websites

• Use AWS Elastic Beanstalk for easy deployment and scaling

Load balancers distribute incoming network or application traffic across multiple servers to ensure no single server is overwhelmed.

• Application load balancer operates at the application layer and directs traffic based on content of the request.

• Network load balancer operates at the transport layer and routes connections based on IP protocol data.

• Load balancers improve application availability, scalability, and reliability by distributing traffic efficiently.

• Examples: AWS Appli...read more

CI/CD process is a software development practice where code changes are automatically built, tested, and deployed.

• Continuous Integration (CI) involves automatically building and testing code changes frequently.

• Continuous Deployment (CD) involves automatically deploying code changes to production.

• CI/CD helps in reducing manual errors, improving code quality, and increasing deployment frequency.

• Popular CI/CD tools include Jenkins, GitLab CI/CD, and CircleCI.

Playbook to copy files in Ansible

• Use the 'copy' module in Ansible to copy files

• Specify source and destination paths in the playbook

• Run the playbook using 'ansible-playbook' command

Terraform is an infrastructure as code tool used for building, changing, and versioning infrastructure safely and efficiently.

• Terraform allows users to define infrastructure in a declarative configuration language.

• It automates the process of provisioning and managing cloud resources.

• Terraform supports multiple cloud providers such as AWS, Azure, and Google Cloud.

• It helps in creating reproducible infrastructure and enables infrastructure changes to be versioned.

Kubernetes architecture is a container orchestration platform that manages containerized applications across a cluster of nodes.

• Kubernetes follows a master-slave architecture with a master node and multiple worker nodes.

• Master node components include API server, scheduler, controller manager, and etcd.

• Worker node components include kubelet, kube-proxy, and container runtime (e.g. Docker).

• Pods are the smallest deployable units in Kubernetes, consisting of one or more container...read more

Deployment refers to the process of releasing a new version of software, while stateful refers to systems that retain data between sessions.

• Deployment involves releasing new versions of software to servers or environments.

• Stateful systems retain data between sessions, unlike stateless systems.

• Stateful applications require more complex management and scaling compared to stateless applications.

• Examples of stateful applications include databases and file systems.

• Examples of depl...read more

Find the second largest number in an array of strings.

• Convert the array of strings to an array of integers for comparison.

• Sort the array in descending order and return the second element.

• Handle cases where there may be duplicates of the largest number.

A Linux based server is a computer system that runs on a Linux operating system, providing services and resources to clients over a network.

• Linux based servers are commonly used for web hosting, email hosting, file sharing, and other network services.

• They are known for their stability, security, and flexibility compared to other operating systems.

• Examples of popular Linux server distributions include Ubuntu Server, CentOS, and Red Hat Enterprise Linux.

Blue green deployment is a software release strategy that reduces downtime and risk by running two identical production environments.

• In blue green deployment, one environment (blue) is currently live and serving production traffic, while the other environment (green) is idle.

• The new version of the software is deployed to the idle environment (green) and tested thoroughly.

• Once the new version is deemed stable, traffic is switched from the blue environment to the green environm...read more

DevOps is a software development methodology that combines software development (Dev) with IT operations (Ops) to shorten the systems development life cycle.

• DevOps focuses on collaboration, automation, and monitoring throughout the software development lifecycle.

• It aims to increase the speed of software delivery, improve reliability, and build scalable and secure systems.

• Tools commonly used in DevOps include Jenkins, Docker, Kubernetes, and Ansible.

ALB stands for Application Load Balancer, which distributes incoming application traffic across multiple targets, such as EC2 instances.

• ALB routes traffic based on rules defined by the user

• Supports path-based routing, host-based routing, and routing based on HTTP headers

• Can handle WebSocket traffic, HTTP/2, and gRPC protocols

• Provides SSL termination, content-based routing, and sticky sessions

kubeadm is a tool used to bootstrap Kubernetes clusters.

• kubeadm helps in setting up a minimum viable Kubernetes cluster.

• It automates the process of configuring the cluster's control plane.

• It is part of the Kubernetes project and is used for cluster initialization.

• kubeadm simplifies the process of creating a Kubernetes cluster by handling complex tasks like TLS certificate generation.

Version control tool is a system that records changes to a file or set of files over time so that you can recall specific versions later.

• Tracks changes made to files

• Allows multiple users to collaborate on a project

• Helps in reverting back to previous versions if needed

• Examples: Git, SVN, Mercurial

Two-tier architecture consists of presentation layer and data layer.

• Presentation layer handles user interface and client-side logic.

• Data layer manages data storage and retrieval.

• Example: Web application with frontend (presentation layer) and backend database (data layer).

Kubernetes is an open-source container orchestration platform for automating deployment, scaling, and management of containerized applications.

• Kubernetes automates the deployment, scaling, and management of containerized applications.

• It provides features like self-healing, load balancing, and service discovery.

• Kubernetes uses declarative configuration to define the desired state of the application.

• It supports horizontal scaling by adding or removing containers based on resour...read more

AWS offers a wide range of services for cloud computing, storage, databases, machine learning, and more.

• EC2 (Elastic Compute Cloud) - virtual servers in the cloud

• S3 (Simple Storage Service) - scalable object storage

• RDS (Relational Database Service) - managed relational databases

• Lambda - serverless computing

• SNS (Simple Notification Service) - push notifications

• DynamoDB - NoSQL database

• Elastic Beanstalk - easy deployment and scaling of web applications

• IAM (Identity and Access M...read more