LearnThatStack Ace your next interview
Get Pro
Sign in
Topic · part of System Design Concepts
Load Balancing.
26 Qs 3 free
Change topic Change
Drill · questions

All questions

of 26
Beginner 5
01

What is load balancing and why is it necessary?

Beginner ·

Answer it yourself first - out loud, or typed below.

How should your speech become text?

Listening… your words appear above as you speak - tap Stop when you're done.

Recording · cr - tap Stop & transcribe when you're done.

Transcribing with AI…

Voice:

Keep going - a few more words and AI can grade it.

Last attempt -

Your answer

Re-explain

Load balancing is the process of distributing incoming network traffic or computational workload across multiple servers or resources to ensure no single server becomes overwhelmed. It's necessary for several reasons:

  • Improved availability: If one server fails, others can continue serving requests
  • Better performance: Distributes load to prevent server overload and reduce response times
  • Scalability: Allows adding more servers to handle increased traffic
  • Resource utilization: Ensures efficient use of all available servers
    Think of it like having multiple checkout counters in a store instead of just one - customers get served faster and if one counter breaks down, others are still available.
Rewriting in plainer words…

This answer doesn't lend itself to a diagram - it reads best . No credits were charged.

The model's verdict: “”

The interactive diagram is below the answer - jump to diagram ↓

This answer is explained by a shared concept diagram - open →

Tailored explanation · switch back to · ·
Point the redraw:
How well did you know this?
AI:

Open full page ↗
02

What are the main types of load balancers based on the OSI layer they operate on?

Beginner ·

Answer it yourself first - out loud, or typed below.

How should your speech become text?

Listening… your words appear above as you speak - tap Stop when you're done.

Recording · cr - tap Stop & transcribe when you're done.

Transcribing with AI…

Voice:

Keep going - a few more words and AI can grade it.

Last attempt -

Your answer

Re-explain

There are two main types:
Layer 4 (Transport Layer) Load Balancers:

  • Operate at the TCP/UDP level
  • Make routing decisions based on IP address and port numbers
  • Faster and more efficient
  • Cannot inspect application data
  • Example: AWS Network Load Balancer
    Layer 7 (Application Layer) Load Balancers:
  • Operate at the HTTP/HTTPS level
  • Can make routing decisions based on content (headers, URLs, cookies)
  • More intelligent routing capabilities
  • Can perform SSL termination
  • Example: AWS Application Load Balancer
Rewriting in plainer words…

This answer doesn't lend itself to a diagram - it reads best . No credits were charged.

The model's verdict: “”

The interactive diagram is below the answer - jump to diagram ↓

This answer is explained by a shared concept diagram - open →

Tailored explanation · switch back to · ·
Point the redraw:
How well did you know this?
AI:

Open full page ↗
03

Explain the difference between hardware and software load balancers.

Beginner ·

Answer it yourself first - out loud, or typed below.

How should your speech become text?

Listening… your words appear above as you speak - tap Stop when you're done.

Recording · cr - tap Stop & transcribe when you're done.

Transcribing with AI…

Voice:

Keep going - a few more words and AI can grade it.

Last attempt -

Your answer

Re-explain
  • Dedicated physical appliances (F5, Citrix NetScaler)
  • High performance and reliability
  • Expensive and less flexible
  • Vendor lock-in
  • Difficult to scale quickly

Software Load Balancers:

  • Run on standard servers or virtual machines
  • More cost-effective and flexible
  • Easier to configure and update
  • Can be cloud-native
  • Examples: HAProxy, NGINX, Traefik

Most modern applications prefer software load balancers due to their flexibility and integration with cloud environments.

Rewriting in plainer words…

This answer doesn't lend itself to a diagram - it reads best . No credits were charged.

The model's verdict: “”

The interactive diagram is below the answer - jump to diagram ↓

This answer is explained by a shared concept diagram - open →

Tailored explanation · switch back to · ·
Point the redraw:
How well did you know this?
AI:

Open full page ↗
04

What is the Round Robin load balancing algorithm?

Part of Pro
05

What are health checks in load balancing?

Part of Pro
Intermediate 7
06

Explain the Least Connections load balancing algorithm.

Part of Pro
07

What is session persistence (sticky sessions) and when should you use it?

Part of Pro
08

What is SSL termination and what are its benefits?

Part of Pro
09

Explain the Weighted Round Robin algorithm.

Part of Pro
10

What is the difference between a reverse proxy and a load balancer?

Part of Pro
11

What are the different load balancing algorithms and their use cases?

Part of Pro
12

How do you handle failover scenarios in load balancing?

Part of Pro
Expert 14
13

How do you implement global load balancing and what are the challenges?

Part of Pro
14

Explain load balancing strategies for microservices architectures.

Part of Pro
15

How do you troubleshoot load balancer performance issues?

Part of Pro
16

What are the security considerations for load balancers?

Part of Pro
17

How do you implement auto-scaling with load balancers?

Part of Pro
18

How do you design load balancing for high availability across multiple data centers?

Part of Pro
19

What are the performance optimization techniques for load balancers?

Part of Pro
20

How do you implement health checks for complex applications with dependencies?

Part of Pro
21

What are the challenges and solutions for load balancing WebSocket connections?

Part of Pro
22

How do you implement blue-green deployments with load balancers?

Part of Pro
23

What are the key metrics and monitoring strategies for load balancers?

Part of Pro
24

How do you handle load balancing for applications with varying resource requirements?

Part of Pro
25

How do you implement disaster recovery strategies for load-balanced systems?

Part of Pro
26

How do you perform rolling updates with zero downtime?

Part of Pro

No matches

Try a different filter or search term.

Learn · video

Load Balancing, in short videos.

2:44 Pro
Performance vs Scalability

Beyond this topic. Preparing for a different stack? These are the biggest System Design Concepts topics we cover.

More in System Design Concepts
Microservices 52 questions Design Patterns 45 questions API Design 45 questions Software Architecture 42 questions Domain-Driven Design (DDD) 38 questions Messaging & Queues 38 questions
Pro · $10/mo

23 of 26 Load Balancing answers are gated.

Full answers, code samples, AI explanations - simpler, deeper, or as an interactive diagram. Cancel anytime.

  • Full answers + code
  • AI explain - simpler, deeper, or visualized
  • 1,000 AI credits / month
  • Cancel anytime
Get Pro → See plans & pricing →

Change topic

Pick a different technology or stack. Your current topic stays put until you choose a new one.

Technologies
No technologies match “”.
Cross-cutting topics
No topics match “”.
Search everything for “” →
React 103 Angular 89 Vue.js 102 CSS3 104 HTML5 84 Tailwind CSS 72 Bootstrap 99 JavaScript 115 TypeScript 99 Next.js 94 Vite 49 Webpack 49 Redux 49 Redux Toolkit 49 React Query 49 Playwright 49 Cypress 39 Jest 49 GraphQL 57 Blazor
ASP.NET Core 62 Entity Framework Core 52 C# 99 Java 89 Spring Framework 49 Spring Boot 36 Hibernate 38 Golang 67 Python 52 Django 47 Flask 56 FastAPI 46 Node.js 57 Express.js 44 Nest.js 44 Laravel 50 Ruby on Rails 65 REST 44 gRPC 31 Apache Kafka 37 RabbitMQ 31 PHP 78 Ruby 85 Sidekiq 50 Celery 50 Contentful 40
SQL Fundamentals 41 Database Design 35 MySQL 35 PostgreSQL 36 SQL Server 35 Oracle 35 Snowflake 32 InfluxDB 34 MongoDB 52 DynamoDB 35 Cassandra 35 Redis 26 Neo4j 29 Elasticsearch 39 SQLAlchemy 36 Liquibase 24 Flyway 27
Swift 51 SwiftUI 41 UIKit 39 Java 49 Jetpack Compose 29 Android Jetpack Libraries 34 Flutter 49 React Native 51 Firebase 36 SQLite 30 Dart
Design Patterns 45 SOLID Principles 24 Software Architecture 42 API Design 45 Microservices 52 Distributed Systems Fundamentals 34 CAP Theorem & Consistency Models 20 Event-Driven Architecture 34 Domain-Driven Design 38 Messaging & Queues 38 Caching 22 Load Balancing 26 Data Partitioning & Sharding 25 Replication Strategies 26 Rate Limiting & Throttling 22 Resilience Patterns 22 Security Architecture 25 Observability & Monitoring 27 Serverless Architecture 35 Container Orchestration 34
Software Testing 50 Unit Testing 32 Integration Testing 20 Test-Driven Development 33 Behavior-Driven Development 30 API Testing 21 UI Testing 31 Selenium 32 Load Testing 20 Stress Testing 28 Test Automation 36 JUnit 5 22 NUnit / xUnit 37 PyTest 33 Mockito 29 Testcontainers 28
Docker 38 Kubernetes Helm 28 Jenkins 25 GitHub Actions 23 GitLab CI 31 Argo Workflows 22 Argo CD 22 Terraform 32 AWS CloudFormation 40 Ansible 27 Prometheus 32 Grafana Kibana 26 Jaeger 25 OpenTelemetry 25 HashiCorp Vault 20 Sonatype Nexus 24 JFrog Artifactory 22 Vercel
Windows Administration 50 Linux Administration 52 Shell Scripting 32 PowerShell 40 Python for Automation 30 System Administration Fundamentals 42 Networking 52 Firewall Management 1 Identity & Access Management 30 Security Hardening 27 SSL/TLS & PKI 22 Bastion Hosts & SSH Hardening 1 KVM/QEMU 30 KUB Kubernetes Administration 40 Cloud Platforms 1 ELK Stack 1 Storage Management Backup & Disaster Recovery 30 High Availability & Clustering 30 Time Synchronization Patch Management 15 Container Security 28 Apache Administration
Cybersecurity Fundamentals 40 Secure Coding Practices 28 OWASP Top 10 17 Threat Modeling 25 Zero-Trust Architecture 28 Authentication & Authorization 24 OAuth 2.0 / OpenID Connect JWT & Token-Based Auth 18 Multi-Factor Authentication 15 Secrets Management 18 Encryption 15 TLS / SSL & PKI 20
Cryptocurrency Basics 32 Blockchain Architecture 30 Distributed Ledger Technology 28 Consensus Algorithms 20 Bitcoin 25 Ethereum 30 Layer-2 Scaling 9 Solidity 40 Hardhat 22 Foundry 21 OpenZeppelin Contracts 17 Web3.js / Ethers.js 22 Smart Contract Security 15 Slither 17 DeFi Fundamentals 28 Uniswap & AMMs Lending Protocols 17 Chainlink Oracles 16 IPFS 9 MetaMask & Browser Wallets 18 Tokenomics & Incentive Models 18 Crypto Regulations & KYC/AML 17
By role
Stacks & frameworks

MEAN

MongoDB, Express, Angular, Node.js
MongoDB 52 Express.js 44 Angular 89 Node.js 57 TypeScript 99

MERN

MongoDB, Express, React, Node.js
MongoDB 52 Express.js 44 React 103 Node.js 57 Redux 49

LAMP

Linux, Apache, MySQL, PHP
Linux Administration 52 Apache Administration MySQL 35 PHP 78 Laravel 50

Django

Python Full-Stack Development
Python 52 Django 47 PostgreSQL 36 Redis 26 Celery 50 Docker 38

Ruby on Rails

Convention over Configuration
Ruby 85 Ruby on Rails 65 PostgreSQL 36 Redis 26 Sidekiq 50

JAM

JavaScript, APIs, and Markup
JavaScript 115 Next.js 94 GraphQL 57 Tailwind CSS 72 Vercel Contentful 40

Serverless on AWS

Serverless Architecture on AWS
Serverless Architecture 35 API Design 45 DynamoDB 35 AWS CloudFormation 40 Node.js 57
Cross-cutting topics 43 topics

Interviewers also test these - they're common to every stack, whichever one you picked above.

Flutter Mobile

Flutter Cross-Platform Mobile Development
Flutter 49 Dart Firebase 36 API Design 45 SQLite 30
Cross-cutting topics 44 topics

Interviewers also test these - they're common to every stack, whichever one you picked above.

Spring Boot

Enterprise Java Development
Java 89 Spring Boot 36 PostgreSQL 36 Redis 26 Apache Kafka 37 Docker 38 Kubernetes

.NET

Microsoft Ecosystem
C# 99 ASP.NET Core 62 Entity Framework Core 52 SQL Server 35 NUnit / xUnit 37 Blazor

Vue

Vue.js, Vite, TypeScript, Tailwind, Node.js
Vue.js 102 Vite 49 TypeScript 99 Tailwind CSS 72 Node.js 57

Go Backend

Golang, gRPC, PostgreSQL, Redis, RabbitMQ
Golang 67 gRPC 31 PostgreSQL 36 Redis 26 RabbitMQ 31 Docker 38

FastAPI

Python, FastAPI, SQLAlchemy, PostgreSQL
Python 52 FastAPI 46 SQLAlchemy 36 PostgreSQL 36 Redis 26 Docker 38

React Native

React, TypeScript, Redux, Firebase
React Native 51 React 103 TypeScript 99 Redux 49 Firebase 36

iOS Native

Swift, SwiftUI, UIKit, Firebase
Swift 51 SwiftUI 41 UIKit 39 Firebase 36 SQLite 30

Android Native

Java, Jetpack Compose, Firebase
Java 49 Jetpack Compose 29 Android Jetpack Libraries 34 Firebase 36 SQLite 30

Web3 / Ethereum

Solidity, Ethereum, Hardhat, Foundry
Solidity 40 Ethereum 30 Hardhat 22 Foundry 21 Web3.js / Ethers.js 22 OpenZeppelin Contracts 17

DevOps / Platform

Docker, Kubernetes, Terraform, CI/CD
Docker 38 Kubernetes Terraform 32 GitHub Actions 23 Prometheus 32 Helm 28

Core SWE Interview Prep

Data structures, algorithms, OS, concurrency, networking, git
Big-O & Complexity Analysis Arrays, Strings & Hash Tables Linked Lists, Stacks & Queues Trees, BSTs & Heaps Graphs Sorting, Searching & Recursion Operating Systems Concurrency & Multithreading Networking for Developers Git & Version Control API Design 45 Distributed Systems Fundamentals 34
Cross-cutting topics 43 topics

Interviewers also test these - they're common to every stack, whichever one you picked above.

Cross-cutting topics 45 topics

Interviewers also test these - they're common to every stack, whichever one you picked above.