20+ Devops Consultant Interview Questions and Answers

AWS offers three types of load balancers: Application, Network, and Classic. Auto-Scaling helps to automatically adjust resources based on demand. S3 offers four storage classes: Standard, Intelligent-Tiering, Standard-Infrequent Access, and Glacier.

• AWS offers three types of load balancers: Application, Network, and Classic

• Application Load Balancer operates at Layer 7 of the OSI model and is best suited for HTTP/HTTPS traffic

• Network Load Balancer operates at Layer 4 of the OS...read more

Explanation of DevOps CI/CD flow and Git commands

• DevOps CI/CD flow involves continuous integration, testing, and deployment of code changes

• Git stash temporarily saves changes without committing them

• Git commit permanently saves changes to the repository

• Git merge combines changes from different branches

• Git rebase applies changes from one branch onto another

• Git pull fetches changes from a remote repository and merges them into the local branch

• Git fetch only fetches changes from ...read more

To connect to instances, I will use SSH (Secure Shell) protocol.

• SSH (Secure Shell) protocol is a secure way to connect to instances remotely.

• It provides encrypted communication between the client and the server.

• To connect, I will use SSH client software like OpenSSH or PuTTY.

• I will need the public IP address or hostname of the instance.

• I will authenticate using SSH keys or username/password credentials.

Kubernetes architecture includes master nodes, worker nodes, etcd, kubelet, kube-proxy, and more. Communication between pods is established using a network overlay.

• Kubernetes architecture consists of master nodes, which manage the cluster, and worker nodes, where applications run.

• etcd is a distributed key-value store used for storing cluster data.

• kubelet is an agent that runs on each node and ensures containers are running.

• kube-proxy is a network proxy that maintains network ...read more

Kubernetes pods - difference between deployment and daemonset

• Deployment manages a set of identical pods, ensuring availability and scalability

• DaemonSet ensures that all nodes run a copy of a pod, useful for system-level services

• Deployment is suitable for stateless applications, while DaemonSet is suitable for stateful applications

• Deployment can be used for rolling updates, while DaemonSet is not suitable for rolling updates

To ensure high availability of an application, implement redundancy, load balancing, monitoring, and disaster recovery.

• Implement redundancy by having multiple instances of the application running in different servers or data centers.

• Use load balancing to distribute incoming traffic across multiple servers to prevent overload on any single server.

• Set up monitoring tools to constantly check the health and performance of the application and servers.

• Implement disaster recovery pl...read more

DevOps CICD experience with cloud and tool proficiency

• Experience implementing Continuous Integration/Continuous Deployment pipelines using tools like Jenkins, Ansible, Git, Docker, Kubernetes

• Proficiency in cloud platforms such as AWS, GCP, Azure, or on-premise cloud environments

• Familiarity with collaboration tools like Confluence, Jira, Bitbucket, GitHub

• Ability to automate tasks using Python scripting

• Hands-on experience with containerization technologies like Docker

A Dockerfile for Python code with explanations of each command and the difference between ADD & COPY.

• Use a base Python image as the starting point, such as 'python:3.8'.

• Use WORKDIR to set the working directory inside the container.

• Use COPY to add files from the host machine to the container, while ADD can also fetch files from URLs and extract tarballs.

• Use RUN to execute commands during the build process, such as installing dependencies with pip.

• Use CMD to specify the command...read more

Shell script to sort files in descending order

• Use the 'ls' command to list all files in a directory

• Pipe the output of 'ls' to the 'sort' command with the '-r' flag for reverse order

• Example: ls | sort -r

Using Docker image build and deployment in AKS with ACR

• Create a Dockerfile to define the image

• Build the Docker image using 'docker build' command

• Push the image to Azure Container Registry (ACR)

• Create a Kubernetes deployment manifest referencing the image in ACR

• Deploy the application to Azure Kubernetes Service (AKS)

Jenkins pipeline with environment variable

• Define environment variable in Jenkinsfile

• Use 'environment' directive to set environment variables

• Access environment variable using 'env.' syntax

Minimizing downtime can be achieved through proper planning, monitoring, and automation.

• Conduct regular maintenance and updates to prevent system failures

• Implement redundancy and failover mechanisms to ensure continuous operation

• Monitor system performance and proactively address potential issues

• Automate processes to reduce the risk of human error and speed up recovery time

• Have a disaster recovery plan in place to quickly restore services in case of a major outage

A good SCM branching strategy involves clear naming conventions, regular merges, and a well-defined release process.

• Use a naming convention that clearly identifies the purpose of each branch

• Regularly merge changes from development branches into the main branch

• Have a well-defined release process that includes testing and deployment

• Consider using feature toggles to enable/disable new functionality

• Use automation tools to streamline the branching and merging process

DevOps engineers are responsible for automating, monitoring, and maintaining the infrastructure and deployment pipelines.

• Automating build and deployment processes using tools like Jenkins, GitLab CI/CD, or CircleCI

• Monitoring system performance and availability using tools like Prometheus, Grafana, or ELK stack

• Collaborating with development and operations teams to streamline processes and improve efficiency

• Managing infrastructure as code using tools like Terraform or Ansible

• Im...read more

DevOps principles focus on collaboration, automation, measurement, and continuous improvement.

• Collaboration between development and operations teams

• Automation of processes to increase efficiency and reduce errors

• Measurement of performance metrics to identify areas for improvement

• Continuous improvement through feedback and iteration

• Use of tools like Docker, Kubernetes, and Jenkins to support DevOps practices

Subnets on virtual machines refer to dividing a network into smaller segments for better organization and security.

• Subnets help in managing network traffic efficiently

• Each subnet can have its own security policies and access controls

• Subnets can be used to isolate different parts of a network for security reasons

VNet peering allows connecting virtual networks in Azure

• VNet peering enables resources in different virtual networks to communicate securely

• Traffic between peered VNets stays on the Microsoft backbone network

• No public internet, gateways, or encryption needed for communication between peered VNets