Book Image

AWS Certified Developer - Associate Guide

By : Vipul Tankariya, Bhavin Parmar
Book Image

AWS Certified Developer - Associate Guide

By: Vipul Tankariya, Bhavin Parmar

Overview of this book

AWS Certified Developer - Associate Guide starts with a quick introduction to AWS and the prerequisites to get you started. Then, this book gives you a fair understanding of core AWS services and basic architecture. Next, this book will describe about getting familiar with Identity and Access Management (IAM) along with Virtual private cloud (VPC). Moving ahead you will learn about Elastic Compute cloud (EC2) and handling application traffic with Elastic Load Balancing (ELB). Going ahead you we will talk about Monitoring with CloudWatch, Simple storage service (S3) and Glacier and CloudFront along with other AWS storage options. Next we will take you through AWS DynamoDB – A NoSQL Database Service, Amazon Simple Queue Service (SQS) and CloudFormation Overview. Finally, this book covers understanding Elastic Beanstalk and overview of AWS lambda. At the end of this book, we will cover enough topics, tips and tricks along with mock tests for you to be able to pass the AWS Certified Developer - Associate exam and develop as well as manage your applications on the AWS platform.
Table of Contents (29 chapters)
Title Page
Credits
About the Author
Acknowledgments
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface
Index

Introduction to the Elastic Load Balancer


An Elastic Load Balancer (ELB) is an AWS service that automatically distributes incoming network or application traffic to a number of EC2 instances. It monitors the health of each of the EC2 instances associated with it and forwards traffic only to healthy instances. An ELB  provides a single point of contact for the EC2 instances behind the ELB. Each of the EC2 instances is marked with a status, either InService if it is healthy, or OutOfService if it is unhealthy. Traffic is routed only to InService instances. An ELB provides a single point of contact for the application traffic that is hosted on multiple EC2 instances. By routing traffic only to healthy instances, an ELB provides fault tolerance to the application and ensures high availability of the application:

Benefits of using an ELB

An ELB provides high availability, fault tolerance, elasticity, and security to your environment. We will now look at the benefits of an ELB in brief:

  • High availability...