20+ Interview Questions and Answers

Linux commands for monitoring

• top - displays system processes

• htop - interactive process viewer

• vmstat - virtual memory statistics

• iostat - input/output statistics

• netstat - network statistics

• sar - system activity report

• free - displays memory usage

• df - displays disk space usage

• ps - displays information about running processes

Filter students with average marks > 85

• Calculate average marks for each student

• Filter students with average marks > 85

• Return names of filtered students

I am looking for change to explore new challenges and opportunities. Qualys offers a variety of work in cybersecurity and cloud security.

• Seeking new challenges and opportunities to grow professionally

• Interested in cybersecurity and cloud security

• Excited about the diverse range of projects at Qualys

SQL plan can be analyzed using tools like SQL Developer, SQL*Plus, or Oracle Enterprise Manager.

• Use EXPLAIN PLAN to generate a query execution plan

• Analyze the plan for potential performance issues

• Look for full table scans, high cost operations, and missing indexes

• Use SQL tuning tools to optimize the plan

• Consider using hints to force a specific execution plan

Create an enqueue function with enqueue, dequeue, peek, and size operations.

• Create a class Queue with an array to store elements.

• Implement enqueue method to add elements to the queue.

• Implement dequeue method to remove elements from the queue.

• Implement peek method to return the first element in the queue.

• Implement size method to return the number of elements in the queue.

False positives are incorrect alerts that are mistakenly identified as threats, while false negatives are actual threats that are missed by the system.

• False positives are alerts that are incorrectly identified as threats by a security system.

• False negatives are actual threats that are missed by the security system.

• False positives can lead to wasted time and resources investigating non-existent threats.

• False negatives can result in real threats going undetected and causing har...read more

The challenge in analysis is to identify the root cause of performance issues.

• Identify the performance metrics to be analyzed

• Collect and analyze data from various sources

• Use tools like APM, profiling, and monitoring tools

• Identify patterns and anomalies in the data

• Correlate the data to identify the root cause

• Provide recommendations for improvement

SSL certs are used to secure communication over the internet. Netstat command is used to display network connections, routing tables, interface statistics, masquerade connections, and multicast memberships.

• SSL certs are used to encrypt data transmitted between a client and a server to ensure secure communication.

• SSL certs contain information such as the certificate holder's name, the certificate authority that issued the certificate, the certificate's public key, and the digi...read more

OWASP is a non-profit organization focused on improving software security. SSRF is a vulnerability that allows attackers to send requests from the server.

• OWASP stands for Open Web Application Security Project

• OWASP provides resources and tools to improve software security

• SSRF (Server-Side Request Forgery) is a vulnerability that allows attackers to make requests from the server to internal or external resources

• Attackers can exploit SSRF to access sensitive information, bypass ...read more

The 'this' keyword refers to the current object in a method or constructor.

• Used to refer to the current object within a class

• Can be used to pass the current object as a parameter to another method

• Helps differentiate between instance variables and local variables with the same name

React components are reusable UI elements that manage their own state and lifecycle methods control the behavior of components.

• React components are reusable UI elements that can be composed together to build complex user interfaces.

• Components can manage their own state, which allows for dynamic and interactive user interfaces.

• Lifecycle methods in React control the behavior of components at different stages of their lifecycle, such as mounting, updating, and unmounting.

• Example...read more

Network device config can be backed up using tools like TFTP, SCP, or vendor-specific backup solutions.

• Use TFTP (Trivial File Transfer Protocol) to backup device config to a TFTP server.

• Use SCP (Secure Copy Protocol) to securely transfer config files to a remote server.

• Leverage vendor-specific backup solutions like Cisco's Configuration Archive or Juniper's Junos Space Network Director.

• Automate backups using scripts or network management tools like Ansible or SolarWinds.

Code splitting is a technique used to split code into smaller chunks that can be loaded on demand.

• Code splitting helps improve performance by reducing initial load times.

• It allows for lazy loading of code, meaning only necessary code is loaded when needed.

• Commonly used in React applications with tools like React.lazy() and Suspense.

Yes, I am willing to work on hybrid mode.

• I have experience working on hybrid applications using frameworks like Ionic or React Native.

• I am comfortable with developing for both web and mobile platforms.

• I understand the benefits of hybrid development in terms of cost and time efficiency.

I have experience deploying web applications using Docker for containerization and easy deployment.

• Utilized Docker Compose for managing multi-container applications

• Created Dockerfiles to define application environments

• Deployed applications to production servers using Docker Swarm or Kubernetes

Django is a high-level Python web framework that encourages rapid development and clean, pragmatic design. Flask is a lightweight WSGI web application framework.

• Django is a full-featured framework with built-in ORM, admin panel, and authentication system.

• Flask is a microframework that is more lightweight and flexible, allowing developers to choose their own tools and libraries.

• Django follows the 'batteries included' philosophy, while Flask follows the 'minimalistic' approach....read more

To find starting point in a graph, perform a topological sort and return the first node with no incoming edges.

• Perform a topological sort on the graph

• Return the first node with no incoming edges as the starting point

• If there are multiple nodes with no incoming edges, choose any one as the starting point

SSL (Secure Sockets Layer) is a protocol that ensures secure communication over a computer network.

• SSL encrypts data transmitted between a client and a server to prevent eavesdropping.

• Netstat command is used to display active network connections, routing tables, and interface statistics.

• To check SSL connections using netstat, you can use 'netstat -an | findstr :443' for HTTPS connections.

Sorting elements in an array of strings

• Use built-in sorting functions like sort() in most programming languages

• Custom sorting can be implemented based on specific requirements

• Consider the case sensitivity and special characters while sorting

Exploit a vulnerable demo website to demonstrate technical skills.

• Identify the vulnerability in the website (e.g. SQL injection, XSS)

• Exploit the vulnerability to gain unauthorized access or perform malicious actions

• Document the steps taken and potential impact of the exploit

Phases in using Terraform include initialization, planning, applying, and destroying.

• Initialization: Setting up Terraform environment with 'terraform init'

• Planning: Preview changes with 'terraform plan'

• Applying: Execute changes with 'terraform apply'

• Destroying: Remove resources with 'terraform destroy'

Integrating entities involves connecting different systems or components to work together seamlessly.

• Identify the entities that need to be integrated

• Determine the communication protocols and data formats for integration

• Develop APIs or middleware to facilitate communication

• Test the integration to ensure proper functionality

• Monitor and maintain the integration for ongoing performance

The OSI model is a conceptual framework that standardizes the functions of a telecommunication or computing system into seven layers.

• The OSI model stands for Open Systems Interconnection model.

• It divides network communication into seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer has specific functions and interacts with adjacent layers for data transmission.

• The model helps in understanding how data flows in a network and...read more

Python has various datatypes like int, float, str, list, tuple, dict, set, bool.

• int: whole numbers

• float: decimal numbers

• str: text

• list: ordered collection

• tuple: ordered, immutable collection

• dict: key-value pairs

• set: unordered collection with no duplicates

• bool: True or False values

Matrix-based with cross-functional teams and clear reporting lines

• Matrix structure with functional and project-based teams

• Clear reporting lines for accountability

• Cross-functional teams for collaboration and innovation