Day 10 - Elastic Load Balancing

Date: 2025-09-19 (Friday)
Status: “Done”

Lecture Notes

Elastic Load Balancing (ELB)

Overview

  • A fully managed service distributing traffic across multiple targets (EC2, containers, etc.).
  • Supports HTTP, HTTPS, TCP, TLS.
  • Can be deployed in public or private subnets.
  • Provides DNS names; only NLB supports static IPs.
  • Includes health checks and access logs (to S3).
  • Supports sticky sessions (session affinity).
  • Types: Application, Network, Classic, and Gateway Load Balancer.

Application Load Balancer (ALB)

  • Operates at Layer 7 (HTTP/HTTPS).
  • Supports path-based routing (e.g., /mobile vs /desktop).
  • Targets: EC2, Lambda, IP addresses, containers (ECS/EKS).

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ALB Features:

  • Host-based routing
  • Path-based routing
  • HTTP header-based routing
  • Query string parameter-based routing
  • WebSocket support
  • HTTP/2 support

Network Load Balancer (NLB)

  • Operates at Layer 4 (TCP/TLS).
  • Supports static IPs and handles millions of requests per second.
  • Targets: EC2, IP addresses, containers (ECS/EKS).

NLB Features:

  • Ultra-low latency
  • Static IP addresses
  • Preserve source IP
  • Long-lived TCP connections
  • TLS termination

Gateway Load Balancer (GWLB)

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Exploration

AWS Advanced Networking – Specialty Study Guide

  • Official study guide covering exam topics, AWS network design principles, and real-world architecture scenarios.

Hands-On Labs

Lab 20 – AWS Transit Gateway

  1. Preparation Steps → 20-02
  2. Create Transit Gateway → 20-03
  3. Create TGW Attachments → 20-04
  4. Create TGW Route Tables → 20-05
  5. Add TGW Routes to VPC Route Tables → 20-06

Week 2 Summary

  • Hoàn thiện các chủ đề mạng: VPC/Subnets, Security Groups/NACLs.
  • Nắm kết nối liên VPC (Peering, Transit Gateway) và hybrid (VPN, Direct Connect).
  • Tìm hiểu các loại Elastic Load Balancer (ALB, NLB, GWLB) và tính năng chính.
  • Labs: VPC Basics, Hybrid DNS, VPC Peering, Transit Gateway.