Hola9 Sdet Lead Interview Questions and Answers

State management in React involves managing the state and props of components.

• State is used to manage data that changes within a component

• Props are used to pass data from a parent component to a child component

• State can be updated using setState() method

• Props are read-only and cannot be modified within a component

• State and props are used together to create dynamic and interactive UIs

CI/CD pipeline is a process of continuous integration and continuous delivery/deployment of software.

• CI/CD pipeline automates the software delivery process

• It helps in detecting and fixing bugs early in the development cycle

• It ensures that the software is always in a releasable state

• It reduces the time between writing code and deploying it to production

• Examples of CI/CD tools include Jenkins, Travis CI, and CircleCI

Jenkinsfile is a text file that defines the entire build process for a Jenkins pipeline.

• Jenkinsfile is written in Groovy syntax

• It can be stored in a version control system like Git

• It allows for defining stages, steps, and conditions for a pipeline

• Jenkinsfile can be executed on any Jenkins instance

• Example: pipeline { agent { docker 'maven:3-alpine' } stages { stage('Build') { steps { sh 'mvn -B -DskipTests clean package...read more

To connect a machine in a private subnet, use a bastion host or VPN.

• Set up a bastion host in the public subnet to act as a gateway.

• Use SSH tunneling or RDP to connect to the bastion host.

• From the bastion host, connect to the machine in the private subnet.

• Alternatively, set up a VPN to securely connect to the private subnet.

• Configure the security group and network ACLs to allow the necessary traffic.

Ansible playbooks can be verified/validated using various tools and techniques.

• Use Ansible's built-in syntax checker 'ansible-playbook --syntax-check'

• Use Ansible's 'ansible-lint' tool to check for best practices and potential issues

• Use 'ansible-playbook --check' to simulate playbook execution without making changes

• Use 'ansible-playbook --diff' to show the differences between the current and desired state

• Use 'ansible-pl...read more

Inventory is a list of hosts where Ansible runs tasks. Roles are reusable collections of tasks, files, and templates. Variables are used to store data.

• Inventory is a file or directory containing a list of hosts or groups of hosts

• Roles are used to organize tasks, files, and templates into reusable collections

• Variables are used to store data that can be used across multiple tasks and roles

• Example: inventory file can cont...read more

Adding a user in Jenkins

• Go to Jenkins dashboard and click on 'Manage Jenkins'

• Click on 'Manage Users' and then 'Create User'

• Fill in the user details and click 'Create User'

• Assign the necessary permissions to the user

Maven is a build automation tool used for Java projects. Install is for local repository, deploy is for remote repository.

• Maven is used to manage dependencies and build Java projects

• Install command installs the project's artifact (jar, war, etc.) to the local repository

• Deploy command uploads the artifact to a remote repository

• Install is used during development, deploy is used for distribution

• Example: 'mvn install' inst...read more