60+ SF Infra Interview Questions and Answers

Led a project to implement a cloud-based data analytics platform using AWS services and Python tech stack.

• Designed architecture for data analytics platform using AWS services like S3, Glue, and Athena.

• Implemented ETL processes using Python and Apache Spark for data transformation and analysis.

• Integrated machine learning models into the platform for predictive analytics.

• Ensured scalability and performance optimization of the platform through continuous monitoring and tuning.

• Co...read more

Finding overlapping intervals for calculating final payment of store worker

• Identify all the intervals for which the worker is eligible for payment

• Check for overlapping intervals and merge them

• Calculate the final payment based on the merged intervals

Assessing program benefits involves identifying key metrics, collecting data, analyzing results, and comparing against goals.

• Identify key metrics to measure success, such as cost savings, revenue growth, customer satisfaction, etc.

• Collect relevant data to track progress and measure impact of the program.

• Analyze the data to determine if the program is meeting its objectives and delivering expected benefits.

• Compare the results against the initial goals and objectives to assess ...read more

Managing stakeholders expectations and demands is crucial for successful project delivery.

• Establish clear communication channels with stakeholders

• Set realistic expectations from the beginning

• Regularly update stakeholders on project progress

• Address any concerns or issues promptly

• Seek feedback from stakeholders to ensure alignment

Identifying loopholes in a security model and proposing security controls to improve it.

• Identify potential vulnerabilities such as weak authentication methods, lack of encryption, or inadequate access controls

• Implement strong authentication measures like multi-factor authentication to prevent unauthorized access

• Encrypt sensitive data both in transit and at rest to protect it from unauthorized access

• Implement strict access controls to limit who can access certain resources or ...read more

Opex refers to operational expenses, while Capex refers to capital expenses.

• Opex includes day-to-day expenses like salaries, rent, utilities, and maintenance.

• Capex involves investments in assets that provide long-term value, such as equipment, property, and infrastructure.

• Opex is typically incurred regularly and is fully tax-deductible in the year it is incurred.

• Capex is usually depreciated over time as the asset is used to generate revenue.

• Opex is considered a short-term exp...read more

Solution architecture and block diagram involves designing the overall structure of a system and visually representing it.

• Identify key components and their interactions

• Define data flow and communication protocols

• Consider scalability, security, and performance

• Use tools like UML diagrams or flowcharts

• Example: AWS architecture with EC2 instances, S3 storage, and RDS database

Managing conflicting priorities involves prioritizing tasks, communicating effectively, and being flexible.

• Prioritize tasks based on importance and deadlines

• Communicate with stakeholders to understand their needs and expectations

• Be flexible and willing to adjust plans as needed

• Use tools like project management software to track progress and manage tasks

Design a system for companies to schedule events, manage seats, and allow only employees to book shows.

• Create a database to store company information, event schedules, seat availability, and employee details

• Implement an authentication system to verify employee credentials

• Develop a user interface for companies to define event schedules, seat availability, and prices

• Allow employees to search and book shows based on their company affiliation

• Ensure proper validation and error han...read more

It depends on the specific security requirements and resources of the organization.

• Consider the sensitivity of the data being stored and processed.

• Evaluate the organization's budget and resources for maintaining security measures.

• Assess the expertise of the IT team in managing security for both SaaS and on-prem solutions.

• SaaS may offer better scalability and accessibility, but on-prem may provide more control over security measures.

• Hybrid solutions combining both SaaS and on-...read more

Netflix revenue model is based on subscription fees from customers for access to their streaming service.

• Netflix generates revenue primarily through subscription fees paid by customers for access to their streaming service.

• They offer different subscription plans with varying prices and features, such as Basic, Standard, and Premium.

• Netflix also generates revenue through partnerships and licensing deals with other companies for content distribution.

• Revenue is recognized when s...read more

I would design a store that is visually appealing, easy to navigate, and optimized for customer experience.

• Consider the target demographic and their preferences

• Create a layout that encourages flow and exploration

• Utilize strategic lighting and signage to highlight key products

• Incorporate technology for interactive displays or self-checkout options

• Ensure accessibility for all customers, including those with disabilities

Project phases are distinct stages in a project's lifecycle, each with specific goals and deliverables.

• Initiation: Define project scope, objectives, and stakeholders.

• Planning: Create a detailed project plan, including timelines and resources.

• Execution: Implement the project plan and deliver the project's objectives.

• Monitoring and Controlling: Track project progress, identify issues, and make necessary adjustments.

• Closing: Finalize all project activities, deliver the final pro...read more

Program values and benefits are essential for successful project management, ensuring alignment with organizational goals and delivering value to stakeholders.

• Program values define the principles and beliefs that guide decision-making and behavior within the program.

• Benefits are the positive outcomes or results that the program aims to achieve, such as cost savings, increased efficiency, or improved customer satisfaction.

• Aligning program values with organizational values help...read more

I have experienced failures in past projects and have learned valuable lessons from them.

• Recognizing the importance of clear communication and setting expectations early on

• Implementing regular project status updates to stakeholders to avoid surprises

• Documenting lessons learned to prevent repeating the same mistakes in future projects

Schedule and effort estimation is crucial for successful project management.

• Understand the scope of the project and break it down into smaller tasks

• Estimate the time and resources required for each task

• Consider dependencies between tasks and potential risks

• Use historical data or expert judgment to improve accuracy

• Regularly review and update the schedule as needed

Quality is crucial in delivering successful projects. Various tools like Jira, Confluence, and Jenkins are commonly used to ensure high quality.

• Quality assurance processes are essential to maintain high standards in project deliverables

• Tools like Jira are used for issue tracking and project management

• Confluence is used for documentation and collaboration among team members

• Jenkins is used for continuous integration and continuous delivery to automate testing and deployment pro...read more

EVPN is important in VXLAN for efficient Layer 2 and Layer 3 connectivity in data center networks.

• EVPN provides a scalable control plane for VXLAN overlays

• It enables efficient Layer 2 and Layer 3 connectivity between endpoints in a data center network

• EVPN allows for multi-tenancy and seamless VM mobility within the data center

• It simplifies network provisioning and management in large-scale environments

EVPN is used as the control plane in VXLAN to provide efficient and scalable layer 2 and layer 3 connectivity in data center networks.

• EVPN allows for dynamic MAC address learning and distribution across the VXLAN network.

• EVPN provides a scalable solution for layer 2 and layer 3 connectivity in large data center networks.

• EVPN supports multi-tenancy and allows for efficient traffic forwarding in VXLAN environments.

• EVPN simplifies network management and troubleshooting by centra...read more

An offline store management system is a software that helps manage inventory, sales, and customer data in a physical store without an internet connection.

• The system should have a database to store product information, sales data, and customer information.

• It should have a user-friendly interface for employees to input and access data.

• The system should be able to generate reports on sales, inventory levels, and customer data.

• It should have a backup system in case of data loss o...read more

Arrays are fixed in size and contiguous in memory, while linked lists are dynamic and non-contiguous.

• Arrays have constant time access to elements, while linked lists require traversal.

• Arrays are better for random access, while linked lists are better for insertion and deletion.

• Arrays use less memory overhead, while linked lists use more due to pointers.

• Examples: array of integers vs linked list of nodes.

• Examples: array of characters vs linked list of strings.

I would use the stones to create a unique and functional piece of outdoor furniture.

• Use one stone as a base and two as armrests to create a stone bench

• Stack the stones to create a small table for outdoor dining

• Arrange the stones in a circle to create a fire pit for outdoor gatherings

Explaining algorithms for various problem statements

• For sorting: bubble sort, insertion sort, merge sort, quick sort

• For searching: linear search, binary search

• For graph traversal: breadth-first search, depth-first search

• For dynamic programming: Fibonacci sequence, knapsack problem

• For string manipulation: string reversal, palindrome check

Memory management in linked lists involves allocation and deallocation of nodes.

• Dynamic memory allocation is used to create nodes in a linked list.

• Memory leaks can occur if nodes are not properly deallocated.

• Freed memory should be returned to the operating system using free() function.

• Using a garbage collector can automate memory management in linked lists.

Challenging situations in large program execution

• Managing conflicting priorities and deadlines

• Dealing with unexpected changes in scope or requirements

• Handling communication and coordination among multiple teams and stakeholders

• Resolving resource constraints and budget limitations

Code for Boggle game

• Create a 2D grid of letters

• Generate all possible words using the grid and a dictionary

• Implement a search algorithm to find valid words

• Track score based on word length and rarity

• Allow for multiple players and rounds

BGP attributes are used to influence routing decisions in Border Gateway Protocol.

• BGP attributes include AS_PATH, NEXT_HOP, LOCAL_PREF, MED, etc.

• AS_PATH is used to prevent routing loops and determine the best path to a destination.

• NEXT_HOP specifies the next router to reach a particular destination.

• LOCAL_PREF is used to influence outbound traffic from a BGP router.

• MED (Multi-Exit Discriminator) is used to influence inbound traffic from neighboring ASes.

• Other attributes like O...read more

Performing a security architecture review on the provided model.

• Identify potential security vulnerabilities in the architecture

• Evaluate the effectiveness of security controls in place

• Assess the overall security posture of the system

• Recommend improvements to enhance security measures

The important thing in site engineering is proper planning and coordination.

• Proper planning ensures that all tasks are executed efficiently and on time.

• Coordination among different teams and stakeholders ensures smooth workflow and prevents delays.

• Attention to safety measures and adherence to regulations is crucial.

• Effective communication and problem-solving skills are essential for site engineers.

• Quality control and monitoring of construction activities are important for suc...read more

Tesco's annual report highlighted a strong increase in online sales and a focus on sustainability initiatives.

• Tesco reported a 77% increase in online sales during the pandemic.

• The company outlined its commitment to reducing food waste and plastic packaging.

• Tesco's annual report also mentioned investments in renewable energy and community initiatives.

BGP attributes are characteristics used to make routing decisions in Border Gateway Protocol.

• BGP attributes include AS Path, Next Hop, Local Preference, MED, Origin, and Weight.

• AS Path is a list of AS numbers that the route has traversed.

• Next Hop is the IP address of the next router to reach the destination.

• Local Preference is used to influence outbound traffic.

• MED (Multi-Exit Discriminator) is used to influence inbound traffic.

• Origin indicates how the route was learned (IGP,...read more

Designing a highly scalable inventory management system involves utilizing distributed databases, microservices architecture, and efficient data processing techniques.

• Utilize distributed databases to handle large volumes of data and ensure high availability.

• Implement microservices architecture to modularize the system and allow for easy scalability.

• Use efficient data processing techniques such as batch processing and stream processing to handle real-time updates and analytics...read more

Algorithm to find the maximum element in an array of strings

• Iterate through the array and compare each element to find the maximum

• Initialize a variable to store the maximum element and update it as needed

• Return the maximum element at the end of the iteration

A site engineer is responsible for overseeing construction projects, ensuring they are completed on time, within budget, and meet quality standards.

• Supervising and managing construction activities on site

• Ensuring compliance with building codes and regulations

• Coordinating with architects, contractors, and other stakeholders

• Monitoring progress and resolving any issues or delays

• Performing quality control checks and inspections

• Preparing reports and documentation

• Ensuring safety me...read more

Yes, I am willing to relocate for the Senior Reporting Analyst position.

• I am open to moving to a new location for the right opportunity.

• I understand that relocation may be necessary for career growth.

• I have previously relocated for work and am comfortable with the process.

• I am excited about the possibility of exploring a new city or region.

Handle high rated customers with empathy and professionalism.

• Listen actively to the customer's concerns and show empathy.

• Apologize for any inconvenience caused and assure them that their issue will be resolved.

• Offer solutions or alternatives to address their concerns.

• Follow up with the customer to ensure their satisfaction with the resolution.

• Maintain a positive attitude and remain calm, even if the customer is upset.

The schedule of clockwise rotation refers to the order in which objects or events occur in a clockwise direction.

• Clockwise rotation follows the direction of a clock's hands, moving from the top to the right, then down, left, and back to the top.

• The schedule of clockwise rotation can be used to determine the sequence of tasks or events in a system.

• For example, in a manufacturing process, the schedule of clockwise rotation may indicate the order in which different machines or s...read more

FSMO roles are the 5 special roles in Active Directory that are responsible for managing different aspects of the domain.

• There are 5 FSMO roles: Schema Master, Domain Naming Master, RID Master, PDC Emulator, and Infrastructure Master

• Schema Master: responsible for making changes to the schema

• Domain Naming Master: responsible for adding or removing domains in the forest

• RID Master: responsible for allocating RIDs to domain controllers

• PDC Emulator: responsible for time synchroniz...read more

SLA at work refers to the agreed upon level of service that a facility manager is responsible for delivering.

• SLA stands for Service Level Agreement.

• It outlines the specific services to be provided, performance metrics, and expected response times.

• Facility managers ensure compliance with SLAs to meet client expectations.

• Examples of SLAs in facility management include maintenance response times, cleaning frequencies, and equipment uptime.

• SLAs help establish clear expectations a...read more

System Design with High Level Design (HLD) involves creating a high-level architecture for a software system.

• Identify the requirements and constraints of the system

• Break down the system into smaller components/modules

• Define the interactions between the components/modules

• Consider scalability, performance, and security aspects

• Create diagrams like UML diagrams to visualize the design

General Accepted Accounting Principle refers to a common set of accounting standards and procedures used in the preparation of financial statements.

• GAAP ensures consistency and comparability in financial reporting

• GAAP includes principles such as the cost principle, revenue recognition principle, and matching principle

• GAAP is important for investors, creditors, and other stakeholders to make informed decisions based on financial information

Sliding window problem

• Sliding window technique is used to efficiently solve problems involving arrays or strings

• It involves maintaining a window of elements and sliding it through the array or string

• Common applications include finding maximum or minimum subarrays, substring problems, etc.

Return the maximum element of an array

• Iterate through the array and keep track of the maximum element found so far

• Compare each element with the current maximum and update if a larger element is found

• Return the maximum element after iterating through the entire array

A palindrome is a word, phrase, number, or other sequence of characters that reads the same forward and backward.

• Check if the given string is equal to its reverse

• Ignore spaces and punctuation marks while checking for palindrome

• Convert the string to lowercase before checking for palindrome

Design a cab booking system for users to book rides with drivers.

• Create a database to store user information, driver information, and ride details.

• Implement a user interface for users to book rides, view ride history, and track ongoing rides.

• Develop algorithms for matching users with available drivers based on location and availability.

• Include features like fare estimation, real-time tracking, and payment options.

• Ensure security measures for user data and transactions.

• Conside...read more

Design a high level architecture for Twitter

• Use microservices architecture for scalability and maintainability

• Implement a distributed system for handling high traffic

• Use a NoSQL database like MongoDB for storing tweets and user data

• Implement a caching layer using Redis for faster retrieval of tweets

• Use a message queue like Kafka for handling real-time notifications

IFRS 15 is a financial reporting standard that outlines the principles for recognizing revenue from contracts with customers.

• IFRS 15 provides a single, comprehensive revenue recognition model for all contracts with customers.

• It specifies the criteria for recognizing revenue and how to measure the amount of revenue to be recognized.

• The standard requires entities to identify performance obligations in a contract and allocate the transaction price to these obligations.

• IFRS 15 im...read more

Commercial income refers to revenue generated from business activities or sales of products/services.

• Commercial income is essential for the financial sustainability of a business.

• It includes revenue from sales, services, licensing, advertising, and other business activities.

• Examples of commercial income sources include product sales, subscription fees, and sponsorship deals.

Check power source, battery, connections, and hardware issues

• Check if the laptop is plugged in and the power source is working

• Try a different power outlet or power cable

• Remove the battery and try powering on with just the AC adapter

• Check for loose connections or damaged power button

• Test with a different charger or battery if possible

To sort an array in defined order, use the sort() method with a custom compare function.

• Define the desired order in a compare function

• Pass the compare function as an argument to the sort() method

• The compare function should return a negative value if the first argument should come before the second, a positive value if it should come after, and 0 if they are equal

Postman is a popular tool for API testing, allowing users to send requests, receive responses, and automate testing workflows.

• Postman allows users to easily create and send API requests using a user-friendly interface.

• Users can organize their API requests into collections for easier management and sharing.

• Postman supports various authentication methods, including basic authentication, OAuth, and API keys.

• Users can write test scripts in JavaScript to automate testing and valid...read more

Given a list of meeting time intervals, find the minimum number of conference rooms required.

• Sort the intervals based on start time

• Use a min heap to keep track of end times of ongoing meetings

• If the start time of a meeting is greater than the end time of the earliest meeting in the heap, remove that meeting from heap

• Add the end time of the current meeting to the heap

Joins in MS SQL are used to combine rows from two or more tables based on related columns.

• Joins are used to retrieve data from multiple tables in a single query.

• Common types of joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

• Joins are performed based on matching values in specified columns.

• Joins can be used to fetch related data from different tables using foreign key relationships.

• Joins can be used to filter data based on specific conditions using WHERE clause...read more

Slump value of column is a measure of consistency of fresh concrete.

• Slump value is determined by measuring the change in height of the concrete when a cone is removed.

• It indicates the workability of the concrete mix.

• Different slump values are required for different types of construction projects.

• For example, a high slump value is needed for concrete that needs to be pumped long distances.

Developing a web application for a healthcare company to manage patient records and appointments.

• Using React for front-end development

• Implementing RESTful APIs with Node.js for back-end functionality

• Utilizing MongoDB for database management

IT support keys are essential for providing efficient technical assistance to users.

• Effective communication skills are crucial for understanding and addressing user issues

• Strong problem-solving abilities are necessary to troubleshoot and resolve technical issues

• Knowledge of various operating systems, software applications, and hardware components is important for providing accurate support