40 questions · from 2 interviews · 9 asked more than once
Fortinet interview questions
Every question candidates reported from their Fortinet interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Fortinet coding and DSA questions
- 01
Pascal’s Triangle
No specific description given in the post, linked to LeetCode problem.
Easy · Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 02
Best Time to Buy and Sell Stock II
No specific description given in the post, linked to LeetCode problem.
Medium · Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 03
Reverse String Without Extra Space
Reverse a given string without using any extra space.
- 04
Reverse String In-Place
Implement a function to reverse a string in-place without using extra space.
Easy · From Fortinet | SDE | Backend | Dec 2025 | Offer
Fortinet system design questions
- 01
Pub-Sub Consumer Pseudo-code
Wrote pseudo-code for a publish-subscribe consumer.
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 02
Handling Asynchronous Calls
Discussed how asynchronous calls were handled in my projects/systems.
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 03
API Security Mechanisms
Discussed methods and mechanisms for securing APIs.
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 04
Handling Large Traffic
Discussed strategies and mechanisms for controlling and managing large traffic loads.
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 05
Rate Limiter Algorithms
Discussion on various rate limiter algorithms.
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 06
Project Architecture Discussion
Explained the architecture of one of my projects, including design choices, trade-offs, and failure cases.
- 07
Consumer Down Scenario
Discussed what happens if a consumer is down in a distributed system.
- 08
Message Queue Down Scenario
Discussed what happens if a message queue is down in a distributed system.
- 09
CSRF Attack Handling
Discussed how Cross-Site Request Forgery (CSRF) attacks are handled.
- 10
Master's Project Architecture
Discussion on the architecture of my master's project.
- 11
In-depth OAuth 2.0 Discussion
In-depth discussion and questions about OAuth 2.0.
- 12
Recovery Services
Discussion on recovery services in distributed systems.
- 13
Inter-Service Communication
Discussion on how services communicate with each other in a microservices or distributed architecture.
- 14
Pub-Sub Consumer Downtime Handling
Scenario-based question: What happens if a consumer in a pub-sub system goes down, and how is it handled?
- 15
Message Queue Downtime Handling
Scenario-based question: What happens if the message queue itself goes down, and how is it handled?
- 16
CSRF Attack Prevention
Discussion on what CSRF (Cross-Site Request Forgery) attacks are and how they are handled/prevented.
- 17
In-depth OAuth 2.0
Detailed discussion on the OAuth 2.0 protocol, including its various flows, components, and security considerations.
- 18
Inter-Service Communication Methods
Discussion on various methods and patterns for communication between different microservices or components in a distributed system.
Fortinet behavioural and HR questions
- 01
Why Fortinet?
Behavioral question: Why are you interested in working at Fortinet?
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 02
Work Interest
Behavioral question: What kind of work are you interested in?
Asked 2 times · From Fortinet | SDE | Backend | Dec 2025 | Offer
- 03
Role Expectations
Behavioral question: What are your expectations from this role?
- 04
Expectations from the Role
Behavioral question: What are your expectations from this role?
Fortinet other questions
- 01
Implement Missing REST API Feature
Implemented a missing feature in an incomplete REST API using Java + Spring Boot.
- 02
ORM Concepts
Discussion on what is ORM and why it is used, how ORM can be optimized, and lazy loading vs eager loading.
- 03
SQL Optimization and Design
Questions on SQL indexing and joins, and schema design.
- 04
Backend Security
Discussion on SQL injection and how ORM helps prevent it, and other backend security issues.
- 05
Kafka and OAuth 2.0 Basics
Questions on Kafka basics and OAuth 2.0 basics.
- 06
Implement Missing REST API Feature (Java + Spring Boot)
An incomplete REST API was provided where I had to implement a missing feature using Java + Spring Boot.
- 07
What is ORM and its Use Cases
Questions on what Object-Relational Mapping (ORM) is and why it is used.
- 08
ORM Optimization Techniques
Discussion on various techniques to optimize ORM usage.
- 09
Lazy Loading vs Eager Loading in ORM
Detailed discussion comparing lazy loading and eager loading strategies in ORM.
- 10
SQL Indexing and Joins Concepts
Questions regarding SQL indexing and different types of joins.
- 11
Database Schema Design Principles
Discussion on principles and best practices for database schema design.
- 12
SQL Injection Prevention with ORM
Questions about SQL injection vulnerabilities and how ORM frameworks contribute to preventing them.
- 13
Kafka Basics
Fundamental concepts and workings of Kafka.
- 14
OAuth 2.0 Basics
Fundamental concepts and flow of OAuth 2.0.
Fortinet interview questions FAQ
What questions are asked in Fortinet interviews?
Candidates reported 40 distinct questions across 2 Fortinet interviews. 4 coding and DSA questions, 18 system design questions, 4 behavioural and HR questions, 14 other questions.
Which Fortinet interview questions are asked most often?
The most repeated are "Pascal’s Triangle" (2 times), "Best Time to Buy and Sell Stock II" (2 times), "Pub-Sub Consumer Pseudo-code" (2 times), "Handling Asynchronous Calls" (2 times), "API Security Mechanisms" (2 times).